638872497025 has 81 divisors (see below), whose sum is σ = 946264654587. Its totient is φ = 426631699200.

The previous prime is 638872497019. The next prime is 638872497031. The reversal of 638872497025 is 520794278836.

The square root of 638872497025 is 799295.

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

638872497025 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (638872497019) and next prime (638872497031).

It can be written as a sum of positive squares in 13 ways, for example, as 539576924481 + 99295572544 = 734559^2 + 315112^2 .

It is not a de Polignac number, because 638872497025 - 2¹³ = 638872488833 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 1146988047 + ... + 1146988603.

Almost surely, 2^638872497025 is an apocalyptic number.

638872497025 is the 799295-th square number.

638872497025 is the 399648-th centered octagonal number.

It is an amenable number.

638872497025 is a deficient number, since it is larger than the sum of its proper divisors (307392157562).

638872497025 is an frugal number, since it uses more digits than its factorization.

638872497025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1220 (or 610 counting only the distinct ones).

The product of its (nonzero) digits is 40642560, while the sum is 61.

The spelling of 638872497025 in words is "six hundred thirty-eight billion, eight hundred seventy-two million, four hundred ninety-seven thousand, twenty-five".