639352164025 has 81 divisors (see below), whose sum is σ = 882541131591. Its totient is φ = 459338542080.

The previous prime is 639352164019. The next prime is 639352164167. The reversal of 639352164025 is 520461253936.

The square root of 639352164025 is 799595.

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

It can be written as a sum of positive squares in 13 ways, for example, as 13209134761 + 626143029264 = 114931^2 + 791292^2 .

It is not a de Polignac number, because 639352164025 - 2²³ = 639343775417 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 1563208021 + ... + 1563208429.

Almost surely, 2^639352164025 is an apocalyptic number.

639352164025 is the 799595-th square number.

639352164025 is the 399798-th centered octagonal number.

It is an amenable number.

639352164025 is a deficient number, since it is larger than the sum of its proper divisors (243188967566).

639352164025 is an equidigital number, since it uses as much as digits as its factorization.

639352164025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 908 (or 454 counting only the distinct ones).

The product of its (nonzero) digits is 1166400, while the sum is 46.

It can be divided in two parts, 6393521 and 64025, that added together give a palindrome (6457546).

The spelling of 639352164025 in words is "six hundred thirty-nine billion, three hundred fifty-two million, one hundred sixty-four thousand, twenty-five".