21205472992 has 96 divisors (see below), whose sum is σ = 46631458944. Its totient is φ = 9410419200.

The previous prime is 21205472987. The next prime is 21205472993. The reversal of 21205472992 is 29927450212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21205472993) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3933723 + ... + 3939109.

It is an arithmetic number, because the mean of its divisors is an integer number (485744364).

Almost surely, 2^21205472992 is an apocalyptic number.

21205472992 is a gapful number since it is divisible by the number (22) 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 21205472992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23315729472).

21205472992 is an abundant number, since it is smaller than the sum of its proper divisors (25425985952).

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

21205472992 is a wasteful number, since it uses less digits than its factorization.

21205472992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5672 (or 5664 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 43.

The spelling of 21205472992 in words is "twenty-one billion, two hundred five million, four hundred seventy-two thousand, nine hundred ninety-two".