667688520807 has 72 divisors (see below), whose sum is σ = 1246981890960. Its totient is φ = 340306686720.

The previous prime is 667688520799. The next prime is 667688520907. The reversal of 667688520807 is 708025886766.

It is not a de Polignac number, because 667688520807 - 2³ = 667688520799 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667688520907) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1041382 + ... + 1555587.

It is an arithmetic number, because the mean of its divisors is an integer number (17319192930).

Almost surely, 2^667688520807 is an apocalyptic number.

667688520807 is a deficient number, since it is larger than the sum of its proper divisors (579293370153).

667688520807 is a wasteful number, since it uses less digits than its factorization.

667688520807 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2597053 (or 2597043 counting only the distinct ones).

The product of its (nonzero) digits is 54190080, while the sum is 63.

The spelling of 667688520807 in words is "six hundred sixty-seven billion, six hundred eighty-eight million, five hundred twenty thousand, eight hundred seven".