21972249936 has 360 divisors, whose sum is σ = 79528909824. Its totient is φ = 5607221760.

The previous prime is 21972249931. The next prime is 21972249979. The reversal of 21972249936 is 63994227912.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21972249931) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2839705 + ... + 2847431.

Almost surely, 2^21972249936 is an apocalyptic number.

21972249936 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21972249936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39764454912).

21972249936 is an abundant number, since it is smaller than the sum of its proper divisors (57556659888).

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

21972249936 is a wasteful number, since it uses less digits than its factorization.

21972249936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7799 (or 7783 counting only the distinct ones).

The product of its digits is 2939328, while the sum is 54.

The spelling of 21972249936 in words is "twenty-one billion, nine hundred seventy-two million, two hundred forty-nine thousand, nine hundred thirty-six".