18399413 has 2 divisors, whose sum is σ = 18399414. Its totient is φ = 18399412.

The previous prime is 18399377. The next prime is 18399421. The reversal of 18399413 is 31499381.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18037009 + 362404 = 4247^2 + 602^2 .

It is a cyclic number.

It is not a de Polignac number, because 18399413 - 2⁶ = 18399349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18399443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9199706 + 9199707.

It is an arithmetic number, because the mean of its divisors is an integer number (9199707).

Almost surely, 2^18399413 is an apocalyptic number.

It is an amenable number.

18399413 is a deficient number, since it is larger than the sum of its proper divisors (1).

18399413 is an equidigital number, since it uses as much as digits as its factorization.

18399413 is an evil number, because the sum of its binary digits is even.

The product of its digits is 23328, while the sum is 38.

The square root of 18399413 is about 4289.4536948194. The cubic root of 18399413 is about 263.9984169250.

The spelling of 18399413 in words is "eighteen million, three hundred ninety-nine thousand, four hundred thirteen".