667651635720 has 128 divisors (see below), whose sum is σ = 2225937974400. Its totient is φ = 178005835008.

The previous prime is 667651635719. The next prime is 667651635737. The reversal of 667651635720 is 27536156766.

667651635720 is a `hidden beast` number, since 6 + 6 + 7 + 6 + 5 + 1 + 63 + 572 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5760582 + ... + 5875338.

It is an arithmetic number, because the mean of its divisors is an integer number (17390140425).

Almost surely, 2^667651635720 is an apocalyptic number.

667651635720 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

667651635720 is an abundant number, since it is smaller than the sum of its proper divisors (1558286338680).

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

667651635720 is a wasteful number, since it uses less digits than its factorization.

667651635720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120164 (or 120154 counting only the distinct ones).

The product of its (nonzero) digits is 9525600, while the sum is 54.

The spelling of 667651635720 in words is "six hundred sixty-seven billion, six hundred fifty-one million, six hundred thirty-five thousand, seven hundred twenty".