18031907 has 2 divisors, whose sum is σ = 18031908. Its totient is φ = 18031906.

The previous prime is 18031903. The next prime is 18031919. The reversal of 18031907 is 70913081.

It is a weak prime.

It is an emirp because it is prime and its reverse (70913081) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18031907 - 2² = 18031903 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18031907.

It is not a weakly prime, because it can be changed into another prime (18031903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9015953 + 9015954.

It is an arithmetic number, because the mean of its divisors is an integer number (9015954).

Almost surely, 2^18031907 is an apocalyptic number.

18031907 is a deficient number, since it is larger than the sum of its proper divisors (1).

18031907 is an equidigital number, since it uses as much as digits as its factorization.

18031907 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1512, while the sum is 29.

The square root of 18031907 is about 4246.3992982290. The cubic root of 18031907 is about 262.2288998573.

Adding to 18031907 its reverse (70913081), we get a palindrome (88944988).

The spelling of 18031907 in words is "eighteen million, thirty-one thousand, nine hundred seven".