20637724689 has 6 divisors (see below), whose sum is σ = 29810046786. Its totient is φ = 13758483120.

The previous prime is 20637724687. The next prime is 20637724697. The reversal of 20637724689 is 98642773602.

20637724689 is a `hidden beast` number, since 20 + 6 + 377 + 246 + 8 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 19481180625 + 1156544064 = 139575^2 + 34008^2 .

It is not a de Polignac number, because 20637724689 - 2¹ = 20637724687 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20637724687) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1146540252 + ... + 1146540269.

It is an arithmetic number, because the mean of its divisors is an integer number (4968341131).

Almost surely, 2^20637724689 is an apocalyptic number.

It is an amenable number.

20637724689 is a deficient number, since it is larger than the sum of its proper divisors (9172322097).

20637724689 is a wasteful number, since it uses less digits than its factorization.

20637724689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2293080527 (or 2293080524 counting only the distinct ones).

The product of its (nonzero) digits is 6096384, while the sum is 54.

The spelling of 20637724689 in words is "twenty billion, six hundred thirty-seven million, seven hundred twenty-four thousand, six hundred eighty-nine".