22121556 has 24 divisors (see below), whose sum is σ = 54653760. Its totient is φ = 6940032.

The previous prime is 22121543. The next prime is 22121563. The reversal of 22121556 is 65512122.

It is a happy number.

It is a super-2 number, since 2×22121556² = 978726479722272, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54016 + ... + 54423.

It is an arithmetic number, because the mean of its divisors is an integer number (2277240).

Almost surely, 2^22121556 is an apocalyptic number.

It is an amenable number.

22121556 is an abundant number, since it is smaller than the sum of its proper divisors (32532204).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

22121556 is a wasteful number, since it uses less digits than its factorization.

22121556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108463 (or 108461 counting only the distinct ones).

The product of its digits is 1200, while the sum is 24.

The square root of 22121556 is about 4703.3558232394. The cubic root of 22121556 is about 280.7190532173.

Adding to 22121556 its reverse (65512122), we get a palindrome (87633678).

The spelling of 22121556 in words is "twenty-two million, one hundred twenty-one thousand, five hundred fifty-six".