257506517401 has 9 divisors (see below), whose sum is σ = 299552529951. Its totient is φ = 220716827352.

The previous prime is 257506517399. The next prime is 257506517441. The reversal of 257506517401 is 104715605752.

The square root of 257506517401 is 507451.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 180153558025 + 77352959376 = 424445^2 + 278124^2 .

It is not a de Polignac number, because 257506517401 - 2¹ = 257506517399 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257506517441) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3515911 + ... + 3588403.

It is an arithmetic number, because the mean of its divisors is an integer number (33283614439).

Almost surely, 2^257506517401 is an apocalyptic number.

257506517401 is the 507451-st square number.

257506517401 is the 253726-th centered octagonal number.

It is an amenable number.

257506517401 is a deficient number, since it is larger than the sum of its proper divisors (42046012550).

257506517401 is an frugal number, since it uses more digits than its factorization.

257506517401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145000 (or 72500 counting only the distinct ones).

The product of its (nonzero) digits is 294000, while the sum is 43.

The spelling of 257506517401 in words is "two hundred fifty-seven billion, five hundred six million, five hundred seventeen thousand, four hundred one".