18440791 has 2 divisors, whose sum is σ = 18440792. Its totient is φ = 18440790.

The previous prime is 18440743. The next prime is 18440813. The reversal of 18440791 is 19704481.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18440791 - 2⁷ = 18440663 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18440731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9220395 + 9220396.

It is an arithmetic number, because the mean of its divisors is an integer number (9220396).

Almost surely, 2^18440791 is an apocalyptic number.

18440791 is a deficient number, since it is larger than the sum of its proper divisors (1).

18440791 is an equidigital number, since it uses as much as digits as its factorization.

18440791 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 18440791 is about 4294.2742110862. The cubic root of 18440791 is about 264.1961686687.

The spelling of 18440791 in words is "eighteen million, four hundred forty thousand, seven hundred ninety-one".