18311807 has 2 divisors, whose sum is σ = 18311808. Its totient is φ = 18311806.

The previous prime is 18311779. The next prime is 18311819. The reversal of 18311807 is 70811381.

It is a strong prime.

It is an emirp because it is prime and its reverse (70811381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18311807 - 2²⁴ = 1534591 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18311807.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18311827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9155903 + 9155904.

It is an arithmetic number, because the mean of its divisors is an integer number (9155904).

Almost surely, 2^18311807 is an apocalyptic number.

18311807 is a deficient number, since it is larger than the sum of its proper divisors (1).

18311807 is an equidigital number, since it uses as much as digits as its factorization.

18311807 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1344, while the sum is 29.

The square root of 18311807 is about 4279.2297204053. The cubic root of 18311807 is about 263.5787540932.

The spelling of 18311807 in words is "eighteen million, three hundred eleven thousand, eight hundred seven".