21231330972 has 24 divisors (see below), whose sum is σ = 50878686096. Its totient is φ = 6885836928.

The previous prime is 21231330971. The next prime is 21231331021. The reversal of 21231330972 is 27903313212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231330971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23908713 + ... + 23909600.

It is an arithmetic number, because the mean of its divisors is an integer number (2119945254).

Almost surely, 2^21231330972 is an apocalyptic number.

It is an amenable number.

21231330972 is an abundant number, since it is smaller than the sum of its proper divisors (29647355124).

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

21231330972 is a wasteful number, since it uses less digits than its factorization.

21231330972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47818357 (or 47818355 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 33.

The spelling of 21231330972 in words is "twenty-one billion, two hundred thirty-one million, three hundred thirty thousand, nine hundred seventy-two".