21944688918 has 32 divisors (see below), whose sum is σ = 46481475456. Its totient is φ = 6883072128.

The previous prime is 21944688911. The next prime is 21944688923. The reversal of 21944688918 is 81988644912.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21944688911) 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, 488805 + ... + 531807.

It is an arithmetic number, because the mean of its divisors is an integer number (1452546108).

Almost surely, 2^21944688918 is an apocalyptic number.

21944688918 is an abundant number, since it is smaller than the sum of its proper divisors (24536786538).

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

21944688918 is a wasteful number, since it uses less digits than its factorization.

21944688918 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48028.

The product of its digits is 7962624, while the sum is 60.

The spelling of 21944688918 in words is "twenty-one billion, nine hundred forty-four million, six hundred eighty-eight thousand, nine hundred eighteen".