22415521 has 4 divisors (see below), whose sum is σ = 23188500. Its totient is φ = 21642544.

The previous prime is 22415507. The next prime is 22415543. The reversal of 22415521 is 12551422.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7700625 + 14714896 = 2775^2 + 3836^2 .

It is a cyclic number.

It is not a de Polignac number, because 22415521 - 2⁵ = 22415489 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22415492 and 22415501.

It is not an unprimeable number, because it can be changed into a prime (22415021) 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, 386446 + ... + 386503.

It is an arithmetic number, because the mean of its divisors is an integer number (5797125).

Almost surely, 2^22415521 is an apocalyptic number.

It is an amenable number.

22415521 is a deficient number, since it is larger than the sum of its proper divisors (772979).

22415521 is an equidigital number, since it uses as much as digits as its factorization.

22415521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 772978.

The product of its digits is 800, while the sum is 22.

The square root of 22415521 is about 4734.5032474379. The cubic root of 22415521 is about 281.9570420623.

Adding to 22415521 its reverse (12551422), we get a palindrome (34966943).

The spelling of 22415521 in words is "twenty-two million, four hundred fifteen thousand, five hundred twenty-one".