20744070721 has 12 divisors (see below), whose sum is σ = 23187805200. Its totient is φ = 18538608440.

The previous prime is 20744070709. The next prime is 20744070751. The reversal of 20744070721 is 12707044702.

It is a happy number.

It is not a de Polignac number, because 20744070721 - 2⁵ = 20744070689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20744070751) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1445731 + ... + 1460008.

It is an arithmetic number, because the mean of its divisors is an integer number (1932317100).

Almost surely, 2^20744070721 is an apocalyptic number.

It is an amenable number.

20744070721 is a deficient number, since it is larger than the sum of its proper divisors (2443734479).

20744070721 is a wasteful number, since it uses less digits than its factorization.

20744070721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2905820 (or 2905809 counting only the distinct ones).

The product of its (nonzero) digits is 21952, while the sum is 34.

The spelling of 20744070721 in words is "twenty billion, seven hundred forty-four million, seventy thousand, seven hundred twenty-one".