18400285 has 16 divisors (see below), whose sum is σ = 22982400. Its totient is φ = 14129856.

The previous prime is 18400247. The next prime is 18400301. The reversal of 18400285 is 58200481.

It is a de Polignac number, because none of the positive numbers 2^k-18400285 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13986 + ... + 15244.

It is an arithmetic number, because the mean of its divisors is an integer number (1436400).

Almost surely, 2^18400285 is an apocalyptic number.

It is an amenable number.

18400285 is a deficient number, since it is larger than the sum of its proper divisors (4582115).

18400285 is a wasteful number, since it uses less digits than its factorization.

18400285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1380.

The product of its (nonzero) digits is 2560, while the sum is 28.

The square root of 18400285 is about 4289.5553382606. Note that the first 3 decimals coincide. The cubic root of 18400285 is about 264.0025874019.

The spelling of 18400285 in words is "eighteen million, four hundred thousand, two hundred eighty-five".