257373921 has 24 divisors (see below), whose sum is σ = 400386240. Its totient is φ = 146631072.

The previous prime is 257373917. The next prime is 257373967. The reversal of 257373921 is 129373752.

It is not a de Polignac number, because 257373921 - 2² = 257373917 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 257373921.

It is not an unprimeable number, because it can be changed into a prime (257373911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 50335 + ... + 55211.

It is an arithmetic number, because the mean of its divisors is an integer number (16682760).

Almost surely, 2^257373921 is an apocalyptic number.

257373921 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

257373921 is a deficient number, since it is larger than the sum of its proper divisors (143012319).

257373921 is a wasteful number, since it uses less digits than its factorization.

257373921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5253 (or 5246 counting only the distinct ones).

The product of its digits is 79380, while the sum is 39.

The square root of 257373921 is about 16042.8775785393. The cubic root of 257373921 is about 636.0943132750.

The spelling of 257373921 in words is "two hundred fifty-seven million, three hundred seventy-three thousand, nine hundred twenty-one".