22172121 has 6 divisors (see below), whose sum is σ = 32026410. Its totient is φ = 14781408.

The previous prime is 22172119. The next prime is 22172147. The reversal of 22172121 is 12127122.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 15515721 + 6656400 = 3939^2 + 2580^2 .

It is not a de Polignac number, because 22172121 - 2¹ = 22172119 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 22172094 and 22172103.

It is not an unprimeable number, because it can be changed into a prime (22172191) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1231776 + ... + 1231793.

It is an arithmetic number, because the mean of its divisors is an integer number (5337735).

Almost surely, 2^22172121 is an apocalyptic number.

It is an amenable number.

22172121 is a deficient number, since it is larger than the sum of its proper divisors (9854289).

22172121 is a wasteful number, since it uses less digits than its factorization.

22172121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2463575 (or 2463572 counting only the distinct ones).

The product of its digits is 112, while the sum is 18.

The square root of 22172121 is about 4708.7281722350. The cubic root of 22172121 is about 280.9327777465.

Adding to 22172121 its reverse (12127122), we get a palindrome (34299243).

The spelling of 22172121 in words is "twenty-two million, one hundred seventy-two thousand, one hundred twenty-one".