23213021 has 16 divisors (see below), whose sum is σ = 26275200. Its totient is φ = 20357568.

The previous prime is 23212999. The next prime is 23213033. The reversal of 23213021 is 12031232.

23213021 = 35² + 36² + ... + 411².

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 23213021 - 2¹⁰ = 23211997 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 23212987 and 23213005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23213221) 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, 24800 + ... + 25718.

It is an arithmetic number, because the mean of its divisors is an integer number (1642200).

Almost surely, 2^23213021 is an apocalyptic number.

It is an amenable number.

23213021 is a deficient number, since it is larger than the sum of its proper divisors (3062179).

23213021 is a wasteful number, since it uses less digits than its factorization.

23213021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1028.

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 23213021 is about 4817.9893109055. The cubic root of 23213021 is about 285.2619772303.

Adding to 23213021 its reverse (12031232), we get a palindrome (35244253).

The spelling of 23213021 in words is "twenty-three million, two hundred thirteen thousand, twenty-one".