18345987 has 32 divisors (see below), whose sum is σ = 29890560. Its totient is φ = 11028960.

The previous prime is 18345967. The next prime is 18345989. The reversal of 18345987 is 78954381.

It is not a de Polignac number, because 18345987 - 2⁸ = 18345731 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18345989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 66093 + ... + 66369.

It is an arithmetic number, because the mean of its divisors is an integer number (934080).

Almost surely, 2^18345987 is an apocalyptic number.

18345987 is a deficient number, since it is larger than the sum of its proper divisors (11544573).

18345987 is a wasteful number, since it uses less digits than its factorization.

18345987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 520 (or 514 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 18345987 is about 4283.2215679322. The cubic root of 18345987 is about 263.7426469353.

The spelling of 18345987 in words is "eighteen million, three hundred forty-five thousand, nine hundred eighty-seven".