257489820 has 192 divisors, whose sum is σ = 969615360. Its totient is φ = 55378944.

The previous prime is 257489809. The next prime is 257489839. The reversal of 257489820 is 28984752.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 62257 + ... + 66263.

It is an arithmetic number, because the mean of its divisors is an integer number (5050080).

Almost surely, 2^257489820 is an apocalyptic number.

257489820 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 257489820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (484807680).

257489820 is an abundant number, since it is smaller than the sum of its proper divisors (712125540).

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

257489820 is a wasteful number, since it uses less digits than its factorization.

257489820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4049 (or 4041 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 45.

The square root of 257489820 is about 16046.4893356771. The cubic root of 257489820 is about 636.1897796056.

The spelling of 257489820 in words is "two hundred fifty-seven million, four hundred eighty-nine thousand, eight hundred twenty".