18620987 has 32 divisors (see below), whose sum is σ = 24883200. Its totient is φ = 13507200.

The previous prime is 18620983. The next prime is 18620989. The reversal of 18620987 is 78902681.

It is not a de Polignac number, because 18620987 - 2² = 18620983 is a prime.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18620981) 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, 69089 + ... + 69357.

It is an arithmetic number, because the mean of its divisors is an integer number (777600).

Almost surely, 2^18620987 is an apocalyptic number.

18620987 is a deficient number, since it is larger than the sum of its proper divisors (6262213).

18620987 is a wasteful number, since it uses less digits than its factorization.

18620987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347.

The product of its (nonzero) digits is 48384, while the sum is 41.

The square root of 18620987 is about 4315.2041666647. The cubic root of 18620987 is about 265.0539204388.

The spelling of 18620987 in words is "eighteen million, six hundred twenty thousand, nine hundred eighty-seven".