661506006636 has 24 divisors (see below), whose sum is σ = 1715015573040. Its totient is φ = 220502002176.

The previous prime is 661506006587. The next prime is 661506006643. The reversal of 661506006636 is 636600605166.

661506006636 is a `hidden beast` number, since 6 + 6 + 1 + 5 + 0 + 6 + 0 + 0 + 6 + 636 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 661506006591 and 661506006600.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3062527701 + ... + 3062527916.

It is an arithmetic number, because the mean of its divisors is an integer number (71458982210).

Almost surely, 2^661506006636 is an apocalyptic number.

It is an amenable number.

661506006636 is an abundant number, since it is smaller than the sum of its proper divisors (1053509566404).

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

661506006636 is a wasteful number, since it uses less digits than its factorization.

661506006636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6125055630 (or 6125055622 counting only the distinct ones).

The product of its (nonzero) digits is 699840, while the sum is 45.

The spelling of 661506006636 in words is "six hundred sixty-one billion, five hundred six million, six thousand, six hundred thirty-six".