22151231 has 4 divisors (see below), whose sum is σ = 23114352. Its totient is φ = 21188112.

The previous prime is 22151209. The next prime is 22151249. The reversal of 22151231 is 13215122.

It is a happy number.

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 22151231 - 2⁶ = 22151167 is a prime.

It is a super-2 number, since 2×22151231² = 981354069630722, which 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 (22151201) 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, 481526 + ... + 481571.

It is an arithmetic number, because the mean of its divisors is an integer number (5778588).

Almost surely, 2^22151231 is an apocalyptic number.

22151231 is a deficient number, since it is larger than the sum of its proper divisors (963121).

22151231 is an equidigital number, since it uses as much as digits as its factorization.

22151231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 963120.

The product of its digits is 120, while the sum is 17.

The square root of 22151231 is about 4706.5094284406. The cubic root of 22151231 is about 280.8445208194.

Adding to 22151231 its reverse (13215122), we get a palindrome (35366353).

The spelling of 22151231 in words is "twenty-two million, one hundred fifty-one thousand, two hundred thirty-one".