2172305221631 has 4 divisors (see below), whose sum is σ = 2172352043664. Its totient is φ = 2172258399600.

The previous prime is 2172305221621. The next prime is 2172305221637. The reversal of 2172305221631 is 1361225032712.

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

It is a cyclic number.

It is not a de Polignac number, because 2172305221631 - 2²⁶ = 2172238112767 is a prime.

It is a super-2 number, since 2×2172305221631² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2172305221591 and 2172305221600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2172305221637) 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, 23341355 + ... + 23434236.

It is an arithmetic number, because the mean of its divisors is an integer number (543088010916).

Almost surely, 2^{2172305221631} is an apocalyptic number.

2172305221631 is a deficient number, since it is larger than the sum of its proper divisors (46822033).

2172305221631 is an equidigital number, since it uses as much as digits as its factorization.

2172305221631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46822032.

The product of its (nonzero) digits is 30240, while the sum is 35.

The spelling of 2172305221631 in words is "two trillion, one hundred seventy-two billion, three hundred five million, two hundred twenty-one thousand, six hundred thirty-one".