22745521 has 4 divisors (see below), whose sum is σ = 22877172. Its totient is φ = 22613872.

The previous prime is 22745519. The next prime is 22745531. The reversal of 22745521 is 12554722.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12554722 = 2 ⋅6277361.

It can be written as a sum of positive squares in 2 ways, for example, as 21390625 + 1354896 = 4625^2 + 1164^2 .

It is a cyclic number.

It is not a de Polignac number, because 22745521 - 2¹ = 22745519 is a prime.

It is a super-2 number, since 2×22745521² = 1034717451122882, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 22745521.

It is not an unprimeable number, because it can be changed into a prime (22745531) 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, 65566 + ... + 65911.

It is an arithmetic number, because the mean of its divisors is an integer number (5719293).

Almost surely, 2^22745521 is an apocalyptic number.

It is an amenable number.

22745521 is a deficient number, since it is larger than the sum of its proper divisors (131651).

22745521 is a wasteful number, since it uses less digits than its factorization.

22745521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131650.

The product of its digits is 5600, while the sum is 28.

The square root of 22745521 is about 4769.2264571941. The cubic root of 22745521 is about 283.3339587837. Note that the first 3 decimals are identical.

The spelling of 22745521 in words is "twenty-two million, seven hundred forty-five thousand, five hundred twenty-one".