257387040 has 144 divisors (see below), whose sum is σ = 897257088. Its totient is φ = 67158528.

The previous prime is 257387033. The next prime is 257387047. The reversal of 257387040 is 40783752.

257387040 is a `hidden beast` number, since 2 + 573 + 87 + 0 + 4 + 0 = 666.

257387040 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (257387033) and next prime (257387047).

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 257386986 and 257387004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257387047) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 65779 + ... + 69581.

It is an arithmetic number, because the mean of its divisors is an integer number (6230952).

Almost surely, 2^257387040 is an apocalyptic number.

257387040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 257387040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (448628544).

257387040 is an abundant number, since it is smaller than the sum of its proper divisors (639870048).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

257387040 is a wasteful number, since it uses less digits than its factorization.

257387040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3871 (or 3860 counting only the distinct ones).

The product of its (nonzero) digits is 47040, while the sum is 36.

The square root of 257387040 is about 16043.2864463613. The cubic root of 257387040 is about 636.1051208703.

The spelling of 257387040 in words is "two hundred fifty-seven million, three hundred eighty-seven thousand, forty".