18390937 has 2 divisors, whose sum is σ = 18390938. Its totient is φ = 18390936.

The previous prime is 18390929. The next prime is 18390943. The reversal of 18390937 is 73909381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16475481 + 1915456 = 4059^2 + 1384^2 .

It is a cyclic number.

It is not a de Polignac number, because 18390937 - 2³ = 18390929 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18390937.

It is not a weakly prime, because it can be changed into another prime (18391937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9195468 + 9195469.

It is an arithmetic number, because the mean of its divisors is an integer number (9195469).

Almost surely, 2^18390937 is an apocalyptic number.

It is an amenable number.

18390937 is a deficient number, since it is larger than the sum of its proper divisors (1).

18390937 is an equidigital number, since it uses as much as digits as its factorization.

18390937 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 18390937 is about 4288.4655764038. The cubic root of 18390937 is about 263.9578722570.

It can be divided in two parts, 1 and 8390937, that added together give a palindrome (8390938).

The spelling of 18390937 in words is "eighteen million, three hundred ninety thousand, nine hundred thirty-seven".