22810021 has 4 divisors (see below), whose sum is σ = 24564652. Its totient is φ = 21055392.

The previous prime is 22810009. The next prime is 22810031. The reversal of 22810021 is 12001822.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2604996 + 20205025 = 1614^2 + 4495^2 .

It is a cyclic number.

It is not a de Polignac number, because 22810021 - 2⁹ = 22809509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22809977 and 22810004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22810031) 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, 877296 + ... + 877321.

It is an arithmetic number, because the mean of its divisors is an integer number (6141163).

Almost surely, 2^22810021 is an apocalyptic number.

It is an amenable number.

22810021 is a deficient number, since it is larger than the sum of its proper divisors (1754631).

22810021 is a wasteful number, since it uses less digits than its factorization.

22810021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1754630.

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 22810021 is about 4775.9837730043. The cubic root of 22810021 is about 283.6015249152.

Adding to 22810021 its reverse (12001822), we get a palindrome (34811843).

The spelling of 22810021 in words is "twenty-two million, eight hundred ten thousand, twenty-one".