56671985664 has 672 divisors, whose sum is σ = 200370643200. Its totient is φ = 15996911616.

The previous prime is 56671985543. The next prime is 56671985749. The reversal of 56671985664 is 46658917665.

56671985664 is a `hidden beast` number, since 5 + 6 + 67 + 1 + 9 + 8 + 566 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (672).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 682794967 + ... + 682795049.

It is an arithmetic number, because the mean of its divisors is an integer number (298170600).

Almost surely, 2^56671985664 is an apocalyptic number.

56671985664 is a gapful number since it is divisible by the number (54) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 56671985664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100185321600).

56671985664 is an abundant number, since it is smaller than the sum of its proper divisors (143698657536).

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

56671985664 is an frugal number, since it uses more digits than its factorization.

56671985664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145 (or 95 counting only the distinct ones).

The product of its digits is 65318400, while the sum is 63.

The spelling of 56671985664 in words is "fifty-six billion, six hundred seventy-one million, nine hundred eighty-five thousand, six hundred sixty-four".