22990021 has 2 divisors, whose sum is σ = 22990022. Its totient is φ = 22990020.

The previous prime is 22990007. The next prime is 22990039. The reversal of 22990021 is 12009922.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14516100 + 8473921 = 3810^2 + 2911^2 .

It is a cyclic number.

It is not a de Polignac number, because 22990021 - 2¹⁷ = 22858949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22990081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11495010 + 11495011.

It is an arithmetic number, because the mean of its divisors is an integer number (11495011).

Almost surely, 2^22990021 is an apocalyptic number.

It is an amenable number.

22990021 is a deficient number, since it is larger than the sum of its proper divisors (1).

22990021 is an equidigital number, since it uses as much as digits as its factorization.

22990021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 22990021 is about 4794.7910277717. The cubic root of 22990021 is about 284.3455631245.

Adding to 22990021 its reverse (12009922), we get a palindrome (34999943).

The spelling of 22990021 in words is "twenty-two million, nine hundred ninety thousand, twenty-one".