22610721 has 16 divisors (see below), whose sum is σ = 35296128. Its totient is φ = 12604800.

The previous prime is 22610683. The next prime is 22610723. The reversal of 22610721 is 12701622.

It is not a de Polignac number, because 22610721 - 2⁶ = 22610657 is a prime.

It is a super-2 number, since 2×22610721² = 1022489408279682, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (22610723) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12270 + ... + 13991.

It is an arithmetic number, because the mean of its divisors is an integer number (2206008).

Almost surely, 2^22610721 is an apocalyptic number.

22610721 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

22610721 is a deficient number, since it is larger than the sum of its proper divisors (12685407).

22610721 is a wasteful number, since it uses less digits than its factorization.

22610721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26312.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 22610721 is about 4755.0731855567. The cubic root of 22610721 is about 282.7731286991.

22610721 divided by its sum of digits (21) gives a palindrome (1076701).

Subtracting from 22610721 its reverse (12701622), we obtain a palindrome (9909099).

It can be divided in two parts, 226107 and 21, that added together give a triangular number (226128 = T₆₇₂).

The spelling of 22610721 in words is "twenty-two million, six hundred ten thousand, seven hundred twenty-one".