667651820628 has 24 divisors (see below), whose sum is σ = 1677689190688. Its totient is φ = 205431329376.

The previous prime is 667651820611. The next prime is 667651820683. The reversal of 667651820628 is 826028156766.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 2139909526 + ... + 2139909837.

Almost surely, 2^667651820628 is an apocalyptic number.

It is an amenable number.

667651820628 is an abundant number, since it is smaller than the sum of its proper divisors (1010037370060).

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

667651820628 is a wasteful number, since it uses less digits than its factorization.

667651820628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4279819383 (or 4279819381 counting only the distinct ones).

The product of its (nonzero) digits is 11612160, while the sum is 57.

The spelling of 667651820628 in words is "six hundred sixty-seven billion, six hundred fifty-one million, eight hundred twenty thousand, six hundred twenty-eight".