18945637 has 2 divisors, whose sum is σ = 18945638. Its totient is φ = 18945636.

The previous prime is 18945611. The next prime is 18945643. The reversal of 18945637 is 73654981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18714276 + 231361 = 4326^2 + 481^2 .

It is a cyclic number.

It is not a de Polignac number, because 18945637 - 2¹⁹ = 18421349 is a prime.

It is a super-2 number, since 2×18945637² = 717874322671538, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18945593 and 18945602.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18945607) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9472818 + 9472819.

It is an arithmetic number, because the mean of its divisors is an integer number (9472819).

Almost surely, 2^18945637 is an apocalyptic number.

It is an amenable number.

18945637 is a deficient number, since it is larger than the sum of its proper divisors (1).

18945637 is an equidigital number, since it uses as much as digits as its factorization.

18945637 is an evil number, because the sum of its binary digits is even.

The product of its digits is 181440, while the sum is 43.

The square root of 18945637 is about 4352.6586128480. The cubic root of 18945637 is about 266.5854264679.

The spelling of 18945637 in words is "eighteen million, nine hundred forty-five thousand, six hundred thirty-seven".