21949642044 has 72 divisors (see below), whose sum is σ = 61357029552. Its totient is φ = 6560282880.

The previous prime is 21949642037. The next prime is 21949642069. The reversal of 21949642044 is 44024694912.

21949642044 is a `hidden beast` number, since 219 + 4 + 9 + 6 + 420 + 4 + 4 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 350739 + ... + 408554.

It is an arithmetic number, because the mean of its divisors is an integer number (852180966).

Almost surely, 2^21949642044 is an apocalyptic number.

It is an amenable number.

21949642044 is an abundant number, since it is smaller than the sum of its proper divisors (39407387508).

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

21949642044 is a wasteful number, since it uses less digits than its factorization.

21949642044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 759387 (or 759382 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 45.

The spelling of 21949642044 in words is "twenty-one billion, nine hundred forty-nine million, six hundred forty-two thousand, forty-four".