22121645 has 16 divisors (see below), whose sum is σ = 32672640. Its totient is φ = 14001984.

The previous prime is 22121623. The next prime is 22121663. The reversal of 22121645 is 54612122.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 22121645 - 2⁶ = 22121581 is a prime.

It is a super-3 number, since 3×22121645³ (a number of 23 digits) contains 333 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 22121645.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23855 + ... + 24764.

It is an arithmetic number, because the mean of its divisors is an integer number (2042040).

Almost surely, 2^22121645 is an apocalyptic number.

It is an amenable number.

22121645 is a deficient number, since it is larger than the sum of its proper divisors (10550995).

22121645 is a wasteful number, since it uses less digits than its factorization.

22121645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48644.

The product of its digits is 960, while the sum is 23.

The square root of 22121645 is about 4703.3652845596. The cubic root of 22121645 is about 280.7194296821.

Adding to 22121645 its reverse (54612122), we get a palindrome (76733767).

The spelling of 22121645 in words is "twenty-two million, one hundred twenty-one thousand, six hundred forty-five".