20664231660 has 72 divisors (see below), whose sum is σ = 65980540080. Its totient is φ = 5220436608.

The previous prime is 20664231659. The next prime is 20664231703. The reversal of 20664231660 is 6613246602.

20664231660 is a `hidden beast` number, since 2 + 0 + 6 + 642 + 3 + 1 + 6 + 6 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3017667 + ... + 3024506.

It is an arithmetic number, because the mean of its divisors is an integer number (916396390).

Almost surely, 2^20664231660 is an apocalyptic number.

20664231660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20664231660 is an abundant number, since it is smaller than the sum of its proper divisors (45316308420).

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

20664231660 is a wasteful number, since it uses less digits than its factorization.

20664231660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6042207 (or 6042202 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The spelling of 20664231660 in words is "twenty billion, six hundred sixty-four million, two hundred thirty-one thousand, six hundred sixty".