6400640572 has 12 divisors (see below), whose sum is σ = 11202301656. Its totient is φ = 3199982960.

The previous prime is 6400640567. The next prime is 6400640591. The reversal of 6400640572 is 2750460046.

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, 38923 + ... + 119650.

It is an arithmetic number, because the mean of its divisors is an integer number (933525138).

Almost surely, 2^6400640572 is an apocalyptic number.

It is an amenable number.

6400640572 is a deficient number, since it is larger than the sum of its proper divisors (4801661084).

6400640572 is a wasteful number, since it uses less digits than its factorization.

6400640572 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168668 (or 168666 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 34.

The square root of 6400640572 is about 80004.0034748262. The cubic root of 6400640572 is about 1856.6974745420.

The spelling of 6400640572 in words is "six billion, four hundred million, six hundred forty thousand, five hundred seventy-two".