20644334460 has 48 divisors (see below), whose sum is σ = 64226820000. Its totient is φ = 5505155712.

The previous prime is 20644334441. The next prime is 20644334471. The reversal of 20644334460 is 6443344602.

20644334460 is a `hidden beast` number, since 2 + 0 + 644 + 3 + 3 + 4 + 4 + 6 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19114585 + ... + 19115664.

It is an arithmetic number, because the mean of its divisors is an integer number (1338058750).

Almost surely, 2^20644334460 is an apocalyptic number.

20644334460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20644334460 is an abundant number, since it is smaller than the sum of its proper divisors (43582485540).

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

20644334460 is a wasteful number, since it uses less digits than its factorization.

20644334460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38230267 (or 38230259 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 36.

The spelling of 20644334460 in words is "twenty billion, six hundred forty-four million, three hundred thirty-four thousand, four hundred sixty".