21631446225673 has 4 divisors (see below), whose sum is σ = 21693427447300. Its totient is φ = 21569465004048.

The previous prime is 21631446225643. The next prime is 21631446225707. The reversal of 21631446225673 is 37652264413612.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11644658030329 + 9986788195344 = 3412427^2 + 3160188^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21631446225673 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21631446225673.

It is not an unprimeable number, because it can be changed into a prime (21631446225643) 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, 30990610290 + ... + 30990610987.

It is an arithmetic number, because the mean of its divisors is an integer number (5423356861825).

Almost surely, 2^{21631446225673} is an apocalyptic number.

It is an amenable number.

21631446225673 is a deficient number, since it is larger than the sum of its proper divisors (61981221627).

21631446225673 is an equidigital number, since it uses as much as digits as its factorization.

21631446225673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61981221626.

The product of its digits is 8709120, while the sum is 52.

The spelling of 21631446225673 in words is "twenty-one trillion, six hundred thirty-one billion, four hundred forty-six million, two hundred twenty-five thousand, six hundred seventy-three".