18000016 has 10 divisors (see below), whose sum is σ = 34875062. Its totient is φ = 9000000.

The previous prime is 17999987. The next prime is 18000041. The reversal of 18000016 is 61000081.

It can be written as a sum of positive squares in only one way, i.e., 14745600 + 3254416 = 3840^2 + 1804^2 .

It is a Harshad number since it is a multiple of its sum of digits (16), and also a Moran number because the ratio is a prime number: 1125001 = 18000016 / (1 + 8 + 0 + 0 + 0 + 0 + 1 + 6).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 562485 + ... + 562516.

Almost surely, 2^18000016 is an apocalyptic number.

18000016 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

18000016 is a deficient number, since it is larger than the sum of its proper divisors (16875046).

18000016 is a wasteful number, since it uses less digits than its factorization.

18000016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1125009 (or 1125003 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 16.

The square root of 18000016 is about 4242.6425727369. The cubic root of 18000016 is about 262.0742170725.

Adding to 18000016 its reverse (61000081), we get a palindrome (79000097).

The spelling of 18000016 in words is "eighteen million, sixteen", and thus it is an aban number and an uban number.