21722533 has 8 divisors (see below), whose sum is σ = 25332800. Its totient is φ = 18619020.

The previous prime is 21722531. The next prime is 21722543. The reversal of 21722533 is 33522712.

It is not a de Polignac number, because 21722533 - 2¹ = 21722531 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21722498 and 21722507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21722531) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31323 + ... + 32008.

It is an arithmetic number, because the mean of its divisors is an integer number (3166600).

Almost surely, 2^21722533 is an apocalyptic number.

It is an amenable number.

21722533 is a deficient number, since it is larger than the sum of its proper divisors (3610267).

21722533 is an frugal number, since it uses more digits than its factorization.

21722533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63352 (or 63338 counting only the distinct ones).

The product of its digits is 2520, while the sum is 25.

The square root of 21722533 is about 4660.7438247559. The cubic root of 21722533 is about 279.0209556764.

The spelling of 21722533 in words is "twenty-one million, seven hundred twenty-two thousand, five hundred thirty-three".