64729139128828 has 12 divisors (see below), whose sum is σ = 113280451407592. Its totient is φ = 32363295869520.

The previous prime is 64729139128813. The next prime is 64729139128847. The reversal of 64729139128828 is 82882193192746.

It is a happy number.

It is a super-2 number, since 2×64729139128828² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 318309375 + ... + 318512662.

Almost surely, 2^{64729139128828} is an apocalyptic number.

It is an amenable number.

64729139128828 is a deficient number, since it is larger than the sum of its proper divisors (48551312278764).

64729139128828 is a wasteful number, since it uses less digits than its factorization.

64729139128828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 636847452 (or 636847450 counting only the distinct ones).

The product of its digits is 167215104, while the sum is 70.

The spelling of 64729139128828 in words is "sixty-four trillion, seven hundred twenty-nine billion, one hundred thirty-nine million, one hundred twenty-eight thousand, eight hundred twenty-eight".