666426478800 has 120 divisors (see below), whose sum is σ = 2135042014240. Its totient is φ = 177692428800.

The previous prime is 666426478769. The next prime is 666426478847. The reversal of 666426478800 is 8874624666.

It is a tau number, because it is divible by the number of its divisors (120).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11708811 + ... + 11765589.

Almost surely, 2^666426478800 is an apocalyptic number.

666426478800 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

666426478800 is an abundant number, since it is smaller than the sum of its proper divisors (1468615535440).

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

666426478800 is a wasteful number, since it uses less digits than its factorization.

666426478800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66581 (or 66570 counting only the distinct ones).

The product of its (nonzero) digits is 18579456, while the sum is 57.

The spelling of 666426478800 in words is "six hundred sixty-six billion, four hundred twenty-six million, four hundred seventy-eight thousand, eight hundred".