18406487 has 4 divisors (see below), whose sum is σ = 20079816. Its totient is φ = 16733160.

The previous prime is 18406483. The next prime is 18406489. The reversal of 18406487 is 78460481.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18406487 - 2² = 18406483 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18406487.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18406483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 836648 + ... + 836669.

It is an arithmetic number, because the mean of its divisors is an integer number (5019954).

Almost surely, 2^18406487 is an apocalyptic number.

18406487 is a deficient number, since it is larger than the sum of its proper divisors (1673329).

18406487 is a wasteful number, since it uses less digits than its factorization.

18406487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1673328.

The product of its (nonzero) digits is 43008, while the sum is 38.

The square root of 18406487 is about 4290.2781961080. The cubic root of 18406487 is about 264.0322456404.

The spelling of 18406487 in words is "eighteen million, four hundred six thousand, four hundred eighty-seven".