668551971582 has 24 divisors (see below), whose sum is σ = 1580213751480. Its totient is φ = 202591506480.

The previous prime is 668551971553. The next prime is 668551971601. The reversal of 668551971582 is 285179155866.

668551971582 is a `hidden beast` number, since 6 + 6 + 8 + 551 + 9 + 71 + 5 + 8 + 2 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1688262357 + ... + 1688262752.

It is an arithmetic number, because the mean of its divisors is an integer number (65842239645).

Almost surely, 2^668551971582 is an apocalyptic number.

668551971582 is an abundant number, since it is smaller than the sum of its proper divisors (911661779898).

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

668551971582 is a wasteful number, since it uses less digits than its factorization.

668551971582 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3376525128 (or 3376525125 counting only the distinct ones).

The product of its digits is 36288000, while the sum is 63.

The spelling of 668551971582 in words is "six hundred sixty-eight billion, five hundred fifty-one million, nine hundred seventy-one thousand, five hundred eighty-two".