18212865 has 64 divisors (see below), whose sum is σ = 34670592. Its totient is φ = 8064000.

The previous prime is 18212863. The next prime is 18212869. The reversal of 18212865 is 56821281.

It is not a de Polignac number, because 18212865 - 2¹ = 18212863 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (18212861) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 120540 + ... + 120690.

It is an arithmetic number, because the mean of its divisors is an integer number (541728).

Almost surely, 2^18212865 is an apocalyptic number.

18212865 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18212865 is a deficient number, since it is larger than the sum of its proper divisors (16457727).

18212865 is a wasteful number, since it uses less digits than its factorization.

18212865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230.

The product of its digits is 7680, while the sum is 33.

The square root of 18212865 is about 4267.6533364368. The cubic root of 18212865 is about 263.1031753140.

The spelling of 18212865 in words is "eighteen million, two hundred twelve thousand, eight hundred sixty-five".