6660400944 has 40 divisors (see below), whose sum is σ = 17448383232. Its totient is φ = 2188863040.

The previous prime is 6660400939. The next prime is 6660400993. The reversal of 6660400944 is 4490040666.

It is a super-2 number, since 2×6660400944² = 88721881469672182272, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 973764 + ... + 980579.

Almost surely, 2^6660400944 is an apocalyptic number.

It is an amenable number.

6660400944 is an abundant number, since it is smaller than the sum of its proper divisors (10787982288).

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

6660400944 is a wasteful number, since it uses less digits than its factorization.

6660400944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1954425 (or 1954419 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 39.

The square root of 6660400944 is about 81611.2795145377. The cubic root of 6660400944 is about 1881.4822458659.

The spelling of 6660400944 in words is "six billion, six hundred sixty million, four hundred thousand, nine hundred forty-four".