22291813 has 2 divisors, whose sum is σ = 22291814. Its totient is φ = 22291812.

The previous prime is 22291739. The next prime is 22291817. The reversal of 22291813 is 31819222.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18122049 + 4169764 = 4257^2 + 2042^2 .

It is a cyclic number.

It is not a de Polignac number, because 22291813 - 2¹³ = 22283621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22291817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11145906 + 11145907.

It is an arithmetic number, because the mean of its divisors is an integer number (11145907).

Almost surely, 2^22291813 is an apocalyptic number.

It is an amenable number.

22291813 is a deficient number, since it is larger than the sum of its proper divisors (1).

22291813 is an equidigital number, since it uses as much as digits as its factorization.

22291813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1728, while the sum is 28.

The square root of 22291813 is about 4721.4206548453. The cubic root of 22291813 is about 281.4373916270.

It can be divided in two parts, 22291 and 813, that added together give a square (23104 = 152²).

The spelling of 22291813 in words is "twenty-two million, two hundred ninety-one thousand, eight hundred thirteen".