22521251 has 4 divisors (see below), whose sum is σ = 23706600. Its totient is φ = 21335904.

The previous prime is 22521229. The next prime is 22521263. The reversal of 22521251 is 15212522.

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 22521251 - 2¹⁰ = 22520227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22521211) 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, 592646 + ... + 592683.

It is an arithmetic number, because the mean of its divisors is an integer number (5926650).

Almost surely, 2^22521251 is an apocalyptic number.

22521251 is a deficient number, since it is larger than the sum of its proper divisors (1185349).

22521251 is a wasteful number, since it uses less digits than its factorization.

22521251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1185348.

The product of its digits is 400, while the sum is 20.

The square root of 22521251 is about 4745.6560136613. The cubic root of 22521251 is about 282.3996605043.

Adding to 22521251 its reverse (15212522), we get a palindrome (37733773).

The spelling of 22521251 in words is "twenty-two million, five hundred twenty-one thousand, two hundred fifty-one".