639971298225 has 120 divisors (see below), whose sum is σ = 1367954290560. Its totient is φ = 289717274880.

The previous prime is 639971298203. The next prime is 639971298331. The reversal of 639971298225 is 522892179936.

639971298225 is a `hidden beast` number, since 6 + 39 + 97 + 1 + 298 + 225 = 666.

It is not a de Polignac number, because 639971298225 - 2⁵ = 639971298193 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 1240861 + ... + 1679189.

It is an arithmetic number, because the mean of its divisors is an integer number (11399619088).

Almost surely, 2^639971298225 is an apocalyptic number.

It is an amenable number.

639971298225 is an abundant number, since it is smaller than the sum of its proper divisors (727982992335).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

639971298225 is a wasteful number, since it uses less digits than its factorization.

639971298225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438461 (or 438447 counting only the distinct ones).

The product of its digits is 29393280, while the sum is 63.

The spelling of 639971298225 in words is "six hundred thirty-nine billion, nine hundred seventy-one million, two hundred ninety-eight thousand, two hundred twenty-five".