21492919944 has 32 divisors (see below), whose sum is σ = 59702556000. Its totient is φ = 7164306576.

The previous prime is 21492919937. The next prime is 21492919949. The reversal of 21492919944 is 44991929412.

21492919944 is a `hidden beast` number, since 21 + 492 + 9 + 1 + 99 + 44 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (21492919949) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49751914 + ... + 49752345.

It is an arithmetic number, because the mean of its divisors is an integer number (1865704875).

Almost surely, 2^21492919944 is an apocalyptic number.

21492919944 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21492919944 is an abundant number, since it is smaller than the sum of its proper divisors (38209636056).

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

21492919944 is a wasteful number, since it uses less digits than its factorization.

21492919944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99504274 (or 99504264 counting only the distinct ones).

The product of its digits is 1679616, while the sum is 54.

The spelling of 21492919944 in words is "twenty-one billion, four hundred ninety-two million, nine hundred nineteen thousand, nine hundred forty-four".