21344762772 has 72 divisors (see below), whose sum is σ = 56408264640. Its totient is φ = 6805436880.

The previous prime is 21344762741. The next prime is 21344762807. The reversal of 21344762772 is 27726744312.

21344762772 is a `hidden beast` number, since 2 + 13 + 4 + 4 + 7 + 627 + 7 + 2 = 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, 413647 + ... + 462377.

It is an arithmetic number, because the mean of its divisors is an integer number (783448120).

Almost surely, 2^21344762772 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21344762772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28204132320).

21344762772 is an abundant number, since it is smaller than the sum of its proper divisors (35063501868).

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

21344762772 is a wasteful number, since it uses less digits than its factorization.

21344762772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48810 (or 48759 counting only the distinct ones).

The product of its digits is 790272, while the sum is 45.

The spelling of 21344762772 in words is "twenty-one billion, three hundred forty-four million, seven hundred sixty-two thousand, seven hundred seventy-two".