660629938878 has 256 divisors, whose sum is σ = 1857181132800. Its totient is φ = 169443394560.

The previous prime is 660629938867. The next prime is 660629938907. The reversal of 660629938878 is 878839926066.

660629938878 is a `hidden beast` number, since 6 + 606 + 2 + 9 + 9 + 3 + 8 + 8 + 7 + 8 = 666.

It is a super-2 number, since 2×660629938878² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 26665725 + ... + 26690487.

It is an arithmetic number, because the mean of its divisors is an integer number (7254613800).

Almost surely, 2^660629938878 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 660629938878, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (928590566400).

660629938878 is an abundant number, since it is smaller than the sum of its proper divisors (1196551193922).

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

660629938878 is a wasteful number, since it uses less digits than its factorization.

660629938878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24944 (or 24938 counting only the distinct ones).

The product of its (nonzero) digits is 376233984, while the sum is 72.

The spelling of 660629938878 in words is "six hundred sixty billion, six hundred twenty-nine million, nine hundred thirty-eight thousand, eight hundred seventy-eight".