257504251269721 has 9 divisors (see below), whose sum is σ = 269187249628479. Its totient is φ = 246308061225336.

The previous prime is 257504251269709. The next prime is 257504251269737. The reversal of 257504251269721 is 127962152405752.

The square root of 257504251269721 is 16046939.

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

257504251269721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 461142855625 + 257043108414096 = 679075^2 + 16032564^2 .

It is not a de Polignac number, because 257504251269721 - 2⁴¹ = 255305228014169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257504251269751) 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, 368730751 + ... + 369428443.

Almost surely, 2^{257504251269721} is an apocalyptic number.

257504251269721 is the 16046939-th square number.

257504251269721 is the 8023470-th centered octagonal number.

It is an amenable number.

257504251269721 is a deficient number, since it is larger than the sum of its proper divisors (11682998358758).

257504251269721 is an frugal number, since it uses more digits than its factorization.

257504251269721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1395432 (or 697716 counting only the distinct ones).

The product of its (nonzero) digits is 21168000, while the sum is 58.

The spelling of 257504251269721 in words is "two hundred fifty-seven trillion, five hundred four billion, two hundred fifty-one million, two hundred sixty-nine thousand, seven hundred twenty-one".