21522736 has 20 divisors (see below), whose sum is σ = 42273832. Its totient is φ = 10613376.

The previous prime is 21522719. The next prime is 21522737. The reversal of 21522736 is 63722512.

It is not an unprimeable number, because it can be changed into a prime (21522737) 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, 8046 + ... + 10381.

Almost surely, 2^21522736 is an apocalyptic number.

It is an amenable number.

21522736 is a deficient number, since it is larger than the sum of its proper divisors (20751096).

21522736 is a wasteful number, since it uses less digits than its factorization.

21522736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18508 (or 18502 counting only the distinct ones).

The product of its digits is 5040, while the sum is 28.

The square root of 21522736 is about 4639.2602858645. The cubic root of 21522736 is about 278.1628705912.

The spelling of 21522736 in words is "twenty-one million, five hundred twenty-two thousand, seven hundred thirty-six".