257940381 has 4 divisors (see below), whose sum is σ = 343920512. Its totient is φ = 171960252.

The previous prime is 257940313. The next prime is 257940421. The reversal of 257940381 is 183049752.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 257940381 - 2¹⁴ = 257923997 is a prime.

It is a super-2 number, since 2×257940381² = 133066480300850322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257940301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42990061 + ... + 42990066.

It is an arithmetic number, because the mean of its divisors is an integer number (85980128).

Almost surely, 2^257940381 is an apocalyptic number.

It is an amenable number.

257940381 is a deficient number, since it is larger than the sum of its proper divisors (85980131).

257940381 is an equidigital number, since it uses as much as digits as its factorization.

257940381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85980130.

The product of its (nonzero) digits is 60480, while the sum is 39.

The square root of 257940381 is about 16060.5224385759. The cubic root of 257940381 is about 636.5606360467.

The spelling of 257940381 in words is "two hundred fifty-seven million, nine hundred forty thousand, three hundred eighty-one".