20971503720 has 128 divisors (see below), whose sum is σ = 72160128000. Its totient is φ = 5411992320.

The previous prime is 20971503719. The next prime is 20971503769. The reversal of 20971503720 is 2730517902.

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 31 ways as a sum of consecutive naturals, for example, 279715 + ... + 346674.

It is an arithmetic number, because the mean of its divisors is an integer number (563751000).

Almost surely, 2^20971503720 is an apocalyptic number.

20971503720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20971503720 is an abundant number, since it is smaller than the sum of its proper divisors (51188624280).

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

20971503720 is a wasteful number, since it uses less digits than its factorization.

20971503720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 626440 (or 626430 counting only the distinct ones).

The product of its (nonzero) digits is 26460, while the sum is 36.

The spelling of 20971503720 in words is "twenty billion, nine hundred seventy-one million, five hundred three thousand, seven hundred twenty".