639249256122 has 16 divisors (see below), whose sum is σ = 1299457504992. Its totient is φ = 209589919920.

The previous prime is 639249256103. The next prime is 639249256127. The reversal of 639249256122 is 221652942936.

It is a happy number.

It is a super-2 number, since 2×639249256122² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (639249256127) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 873290968 + ... + 873291699.

It is an arithmetic number, because the mean of its divisors is an integer number (81216094062).

Almost surely, 2^639249256122 is an apocalyptic number.

639249256122 is an abundant number, since it is smaller than the sum of its proper divisors (660208248870).

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

639249256122 is a wasteful number, since it uses less digits than its factorization.

639249256122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1746582733.

The product of its digits is 2799360, while the sum is 51.

The spelling of 639249256122 in words is "six hundred thirty-nine billion, two hundred forty-nine million, two hundred fifty-six thousand, one hundred twenty-two".