22221251 has 4 divisors (see below), whose sum is σ = 23930592. Its totient is φ = 20511912.

The previous prime is 22221247. The next prime is 22221259. The reversal of 22221251 is 15212222.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15212222 = 2 ⋅7606111.

It is a cyclic number.

It is not a de Polignac number, because 22221251 - 2² = 22221247 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22221259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 854651 + ... + 854676.

It is an arithmetic number, because the mean of its divisors is an integer number (5982648).

Almost surely, 2^22221251 is an apocalyptic number.

22221251 is a deficient number, since it is larger than the sum of its proper divisors (1709341).

22221251 is a wasteful number, since it uses less digits than its factorization.

22221251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1709340.

The product of its digits is 160, while the sum is 17.

The square root of 22221251 is about 4713.9421931118. The cubic root of 22221251 is about 281.1401259048.

Adding to 22221251 its reverse (15212222), we get a palindrome (37433473).

The spelling of 22221251 in words is "twenty-two million, two hundred twenty-one thousand, two hundred fifty-one".