22170112721 has 4 divisors (see below), whose sum is σ = 22172555700. Its totient is φ = 22167669744.

The previous prime is 22170112693. The next prime is 22170112733. The reversal of 22170112721 is 12721107122.

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 6223474321 + 15946638400 = 78889^2 + 126280^2 .

It is a cyclic number.

It is not a de Polignac number, because 22170112721 - 2²² = 22165918417 is a prime.

It is a super-3 number, since 3×22170112721³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22170112751) 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, 1207826 + ... + 1226043.

It is an arithmetic number, because the mean of its divisors is an integer number (5543138925).

Almost surely, 2^22170112721 is an apocalyptic number.

It is an amenable number.

22170112721 is a deficient number, since it is larger than the sum of its proper divisors (2442979).

22170112721 is an equidigital number, since it uses as much as digits as its factorization.

22170112721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2442978.

The product of its (nonzero) digits is 784, while the sum is 26.

Adding to 22170112721 its reverse (12721107122), we get a palindrome (34891219843).

The spelling of 22170112721 in words is "twenty-two billion, one hundred seventy million, one hundred twelve thousand, seven hundred twenty-one".