18135437 has 2 divisors, whose sum is σ = 18135438. Its totient is φ = 18135436.

The previous prime is 18135427. The next prime is 18135451. The reversal of 18135437 is 73453181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15594601 + 2540836 = 3949^2 + 1594^2 .

It is a cyclic number.

It is not a de Polignac number, because 18135437 - 2⁸ = 18135181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18135427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9067718 + 9067719.

It is an arithmetic number, because the mean of its divisors is an integer number (9067719).

Almost surely, 2^18135437 is an apocalyptic number.

It is an amenable number.

18135437 is a deficient number, since it is larger than the sum of its proper divisors (1).

18135437 is an equidigital number, since it uses as much as digits as its factorization.

18135437 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10080, while the sum is 32.

The square root of 18135437 is about 4258.5721785594. The cubic root of 18135437 is about 262.7298039008.

The spelling of 18135437 in words is "eighteen million, one hundred thirty-five thousand, four hundred thirty-seven".