647499891972 has 96 divisors (see below), whose sum is σ = 1554628723200. Its totient is φ = 209625534720.

The previous prime is 647499891887. The next prime is 647499891979. The reversal of 647499891972 is 279198994746.

It is a super-2 number, since 2×647499891972² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 647499891894 and 647499891903.

It is not an unprimeable number, because it can be changed into a prime (647499891979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 239902279 + ... + 239904977.

It is an arithmetic number, because the mean of its divisors is an integer number (16194049200).

Almost surely, 2^647499891972 is an apocalyptic number.

It is an amenable number.

647499891972 is an abundant number, since it is smaller than the sum of its proper divisors (907128831228).

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

647499891972 is a wasteful number, since it uses less digits than its factorization.

647499891972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4753 (or 4751 counting only the distinct ones).

The product of its digits is 493807104, while the sum is 75.

The spelling of 647499891972 in words is "six hundred forty-seven billion, four hundred ninety-nine million, eight hundred ninety-one thousand, nine hundred seventy-two".