20218688961 has 16 divisors (see below), whose sum is σ = 27690964800. Its totient is φ = 13112877888.

The previous prime is 20218688929. The next prime is 20218688981. The reversal of 20218688961 is 16988681202.

It is not a de Polignac number, because 20218688961 - 2⁵ = 20218688929 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20218688981) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1397955 + ... + 1412343.

It is an arithmetic number, because the mean of its divisors is an integer number (1730685300).

Almost surely, 2^20218688961 is an apocalyptic number.

It is an amenable number.

20218688961 is a deficient number, since it is larger than the sum of its proper divisors (7472275839).

20218688961 is a wasteful number, since it uses less digits than its factorization.

20218688961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27088.

The product of its (nonzero) digits is 663552, while the sum is 51.

The spelling of 20218688961 in words is "twenty billion, two hundred eighteen million, six hundred eighty-eight thousand, nine hundred sixty-one".