22399991 has 2 divisors, whose sum is σ = 22399992. Its totient is φ = 22399990.

The previous prime is 22399987. The next prime is 22400009. The reversal of 22399991 is 19999322.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 22399991 - 2² = 22399987 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22399901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11199995 + 11199996.

It is an arithmetic number, because the mean of its divisors is an integer number (11199996).

Almost surely, 2^22399991 is an apocalyptic number.

22399991 is a deficient number, since it is larger than the sum of its proper divisors (1).

22399991 is an equidigital number, since it uses as much as digits as its factorization.

22399991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 78732, while the sum is 44.

The square root of 22399991 is about 4732.8628756811. The cubic root of 22399991 is about 281.8919115292.

The spelling of 22399991 in words is "twenty-two million, three hundred ninety-nine thousand, nine hundred ninety-one".