18750989 has 2 divisors, whose sum is σ = 18750990. Its totient is φ = 18750988.

The previous prime is 18750931. The next prime is 18751013. The reversal of 18750989 is 98905781.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12709225 + 6041764 = 3565^2 + 2458^2 .

It is a cyclic number.

It is not a de Polignac number, because 18750989 - 2²⁰ = 17702413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18750089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9375494 + 9375495.

It is an arithmetic number, because the mean of its divisors is an integer number (9375495).

Almost surely, 2^18750989 is an apocalyptic number.

It is an amenable number.

18750989 is a deficient number, since it is larger than the sum of its proper divisors (1).

18750989 is an equidigital number, since it uses as much as digits as its factorization.

18750989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 47.

The square root of 18750989 is about 4330.2412172996. The cubic root of 18750989 is about 265.6693131883.

The spelling of 18750989 in words is "eighteen million, seven hundred fifty thousand, nine hundred eighty-nine".