21956019084 has 54 divisors (see below), whose sum is σ = 57631690844. Its totient is φ = 7318664280.

The previous prime is 21956019067. The next prime is 21956019089. The reversal of 21956019084 is 48091065912.

21956019084 is a `hidden beast` number, since 2 + 1 + 9 + 560 + 1 + 9 + 0 + 84 = 666.

It is a tau number, because it is divible by the number of its divisors (54).

It is not an unprimeable number, because it can be changed into a prime (21956019089) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 392062 + ... + 444549.

Almost surely, 2^21956019084 is an apocalyptic number.

It is an amenable number.

21956019084 is an abundant number, since it is smaller than the sum of its proper divisors (35675671760).

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

21956019084 is an frugal number, since it uses more digits than its factorization.

21956019084 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 836639 (or 836616 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 45.

The spelling of 21956019084 in words is "twenty-one billion, nine hundred fifty-six million, nineteen thousand, eighty-four".