21811962072 has 16 divisors (see below), whose sum is σ = 54529905240. Its totient is φ = 7270654016.

The previous prime is 21811962061. The next prime is 21811962079. The reversal of 21811962072 is 27026911812.

It is a self number, because there is not a number n which added to its sum of digits gives 21811962072.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21811962079) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 454415853 + ... + 454415900.

Almost surely, 2^21811962072 is an apocalyptic number.

It is an amenable number.

21811962072 is an abundant number, since it is smaller than the sum of its proper divisors (32717943168).

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

21811962072 is a wasteful number, since it uses less digits than its factorization.

21811962072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 908831762 (or 908831758 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 39.

The spelling of 21811962072 in words is "twenty-one billion, eight hundred eleven million, nine hundred sixty-two thousand, seventy-two".