21944315831 has 4 divisors (see below), whose sum is σ = 21945224064. Its totient is φ = 21943407600.

The previous prime is 21944315821. The next prime is 21944315849. The reversal of 21944315831 is 13851344912.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21944315831 is a prime.

It is a super-2 number, since 2×21944315831² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21944315821) 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, 416855 + ... + 466536.

It is an arithmetic number, because the mean of its divisors is an integer number (5486306016).

Almost surely, 2^21944315831 is an apocalyptic number.

21944315831 is a deficient number, since it is larger than the sum of its proper divisors (908233).

21944315831 is an equidigital number, since it uses as much as digits as its factorization.

21944315831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 908232.

The product of its digits is 103680, while the sum is 41.

The spelling of 21944315831 in words is "twenty-one billion, nine hundred forty-four million, three hundred fifteen thousand, eight hundred thirty-one".