257372820 has 36 divisors (see below), whose sum is σ = 780698100. Its totient is φ = 68632704.

The previous prime is 257372813. The next prime is 257372821. The reversal of 257372820 is 28273752.

It is a happy number.

257372820 is a `hidden beast` number, since 2 + 573 + 7 + 2 + 82 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 116380944 + 140991876 = 10788^2 + 11874^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257372821) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 714745 + ... + 715104.

Almost surely, 2^257372820 is an apocalyptic number.

257372820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

257372820 is an abundant number, since it is smaller than the sum of its proper divisors (523325280).

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

257372820 is a wasteful number, since it uses less digits than its factorization.

257372820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1429864 (or 1429859 counting only the distinct ones).

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

The square root of 257372820 is about 16042.8432642097. The cubic root of 257372820 is about 636.0934062409.

The spelling of 257372820 in words is "two hundred fifty-seven million, three hundred seventy-two thousand, eight hundred twenty".