21522036 has 12 divisors (see below), whose sum is σ = 50218112. Its totient is φ = 7174008.

The previous prime is 21522001. The next prime is 21522037. The reversal of 21522036 is 63022512.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21522037) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 896740 + ... + 896763.

Almost surely, 2^21522036 is an apocalyptic number.

It is an amenable number.

21522036 is an abundant number, since it is smaller than the sum of its proper divisors (28696076).

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

21522036 is a wasteful number, since it uses less digits than its factorization.

21522036 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1793510 (or 1793508 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 21522036 is about 4639.1848421894. The cubic root of 21522036 is about 278.1598549256.

Adding to 21522036 its reverse (63022512), we get a palindrome (84544548).

The spelling of 21522036 in words is "twenty-one million, five hundred twenty-two thousand, thirty-six".