20644540706 has 32 divisors (see below), whose sum is σ = 34808486400. Its totient is φ = 9137197440.

The previous prime is 20644540667. The next prime is 20644540717. The reversal of 20644540706 is 60704544602.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a self number, because there is not a number n which added to its sum of digits gives 20644540706.

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, 267995 + ... + 336318.

It is an arithmetic number, because the mean of its divisors is an integer number (1087765200).

Almost surely, 2^20644540706 is an apocalyptic number.

20644540706 is a deficient number, since it is larger than the sum of its proper divisors (14163945694).

20644540706 is a wasteful number, since it uses less digits than its factorization.

20644540706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 604394.

The product of its (nonzero) digits is 161280, while the sum is 38.

The spelling of 20644540706 in words is "twenty billion, six hundred forty-four million, five hundred forty thousand, seven hundred six".