18940687 has 2 divisors, whose sum is σ = 18940688. Its totient is φ = 18940686.

The previous prime is 18940667. The next prime is 18940693. The reversal of 18940687 is 78604981.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18940687 - 2¹¹ = 18938639 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18940627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9470343 + 9470344.

It is an arithmetic number, because the mean of its divisors is an integer number (9470344).

Almost surely, 2^18940687 is an apocalyptic number.

18940687 is a deficient number, since it is larger than the sum of its proper divisors (1).

18940687 is an equidigital number, since it uses as much as digits as its factorization.

18940687 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96768, while the sum is 43.

The square root of 18940687 is about 4352.0899577100. The cubic root of 18940687 is about 266.5622071764.

The spelling of 18940687 in words is "eighteen million, nine hundred forty thousand, six hundred eighty-seven".