21739431161472 has 32 divisors (see below), whose sum is σ = 57745364023680. Its totient is φ = 7246477053696.

The previous prime is 21739431161467. The next prime is 21739431161473. The reversal of 21739431161472 is 27416113493712.

It is a tau number, because it is divible by the number of its divisors (32).

It is not an unprimeable number, because it can be changed into a prime (21739431161473) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28306550608 + ... + 28306551375.

It is an arithmetic number, because the mean of its divisors is an integer number (1804542625740).

Almost surely, 2^{21739431161472} is an apocalyptic number.

It is an amenable number.

21739431161472 is an abundant number, since it is smaller than the sum of its proper divisors (36005932862208).

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

21739431161472 is an equidigital number, since it uses as much as digits as its factorization.

21739431161472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56613102000 (or 56613101988 counting only the distinct ones).

The product of its digits is 1524096, while the sum is 51.

The spelling of 21739431161472 in words is "twenty-one trillion, seven hundred thirty-nine billion, four hundred thirty-one million, one hundred sixty-one thousand, four hundred seventy-two".