20664624660 has 96 divisors (see below), whose sum is σ = 58390413312. Its totient is φ = 5460255360.

The previous prime is 20664624649. The next prime is 20664624661. The reversal of 20664624660 is 6642646602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20664624661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9379119 + ... + 9381321.

It is an arithmetic number, because the mean of its divisors is an integer number (608233472).

Almost surely, 2^20664624660 is an apocalyptic number.

20664624660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20664624660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29195206656).

20664624660 is an abundant number, since it is smaller than the sum of its proper divisors (37725788652).

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

20664624660 is a wasteful number, since it uses less digits than its factorization.

20664624660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3573 (or 3571 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 42.

The spelling of 20664624660 in words is "twenty billion, six hundred sixty-four million, six hundred twenty-four thousand, six hundred sixty".