257171921 has 8 divisors (see below), whose sum is σ = 264013824. Its totient is φ = 250387200.

The previous prime is 257171917. The next prime is 257171923. The reversal of 257171921 is 129171752.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 257171921 - 2² = 257171917 is a prime.

It is a super-2 number, since 2×257171921² = 132274793901660482, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257171923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5105 + ... + 23246.

It is an arithmetic number, because the mean of its divisors is an integer number (33001728).

Almost surely, 2^257171921 is an apocalyptic number.

It is an amenable number.

257171921 is a deficient number, since it is larger than the sum of its proper divisors (6841903).

257171921 is a wasteful number, since it uses less digits than its factorization.

257171921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28591.

The product of its digits is 8820, while the sum is 35.

The square root of 257171921 is about 16036.5807141049. The cubic root of 257171921 is about 635.9278567814.

The spelling of 257171921 in words is "two hundred fifty-seven million, one hundred seventy-one thousand, nine hundred twenty-one".