21022953 has 8 divisors (see below), whose sum is σ = 32035008. Its totient is φ = 12013104.

The previous prime is 21022921. The next prime is 21022997. The reversal of 21022953 is 35922012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21022953 - 2⁵ = 21022921 is a prime.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (21022913) 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, 500526 + ... + 500567.

It is an arithmetic number, because the mean of its divisors is an integer number (4004376).

Almost surely, 2^21022953 is an apocalyptic number.

It is an amenable number.

21022953 is a deficient number, since it is larger than the sum of its proper divisors (11012055).

21022953 is a wasteful number, since it uses less digits than its factorization.

21022953 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1001103.

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 21022953 is about 4585.0793886257. The cubic root of 21022953 is about 275.9928978429.

Adding to 21022953 its reverse (35922012), we get a palindrome (56944965).

The spelling of 21022953 in words is "twenty-one million, twenty-two thousand, nine hundred fifty-three".