6404862640 has 40 divisors (see below), whose sum is σ = 16245062928. Its totient is φ = 2329040640.

The previous prime is 6404862619. The next prime is 6404862671. The reversal of 6404862640 is 462684046.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 6404862593 and 6404862602.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3638247 + ... + 3640006.

Almost surely, 2^6404862640 is an apocalyptic number.

It is an amenable number.

6404862640 is an abundant number, since it is smaller than the sum of its proper divisors (9840200288).

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

6404862640 is a wasteful number, since it uses less digits than its factorization.

6404862640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7278277 (or 7278271 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 40.

The square root of 6404862640 is about 80030.3857294215. The cubic root of 6404862640 is about 1857.1056305640.

The spelling of 6404862640 in words is "six billion, four hundred four million, eight hundred sixty-two thousand, six hundred forty".