257145515 has 8 divisors (see below), whose sum is σ = 336626928. Its totient is φ = 187014880.

The previous prime is 257145509. The next prime is 257145517. The reversal of 257145515 is 515541752.

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

It is not a de Polignac number, because 257145515 - 2¹⁸ = 256883371 is a prime.

It is a super-2 number, since 2×257145515² = 132247631769230450, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (257145517) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2337632 + ... + 2337741.

It is an arithmetic number, because the mean of its divisors is an integer number (42078366).

Almost surely, 2^257145515 is an apocalyptic number.

257145515 is a deficient number, since it is larger than the sum of its proper divisors (79481413).

257145515 is a wasteful number, since it uses less digits than its factorization.

257145515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4675389.

The product of its digits is 35000, while the sum is 35.

The square root of 257145515 is about 16035.7573877881. The cubic root of 257145515 is about 635.9060906859.

It can be divided in two parts, 257145 and 515, that multiplied together give a triangular number (132429675 = T₁₆₂₇₄).

The spelling of 257145515 in words is "two hundred fifty-seven million, one hundred forty-five thousand, five hundred fifteen".