20744931990 has 32 divisors (see below), whose sum is σ = 49887648000. Its totient is φ = 5520891744.

The previous prime is 20744931979. The next prime is 20744932097. The reversal of 20744931990 is 9913944702.

It is a happy number.

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, 677914 + ... + 707853.

It is an arithmetic number, because the mean of its divisors is an integer number (1558989000).

Almost surely, 2^20744931990 is an apocalyptic number.

20744931990 is an abundant number, since it is smaller than the sum of its proper divisors (29142716010).

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

20744931990 is a wasteful number, since it uses less digits than its factorization.

20744931990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1386276.

The product of its (nonzero) digits is 489888, while the sum is 48.

The spelling of 20744931990 in words is "twenty billion, seven hundred forty-four million, nine hundred thirty-one thousand, nine hundred ninety".