18121256 has 16 divisors (see below), whose sum is σ = 34045440. Its totient is φ = 9042480.

The previous prime is 18121253. The next prime is 18121261. The reversal of 18121256 is 65212181.

It is a super-3 number, since 3×18121256³ (a number of 23 digits) contains 333 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (18121253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2585 + ... + 6551.

It is an arithmetic number, because the mean of its divisors is an integer number (2127840).

Almost surely, 2^18121256 is an apocalyptic number.

It is an amenable number.

18121256 is a deficient number, since it is larger than the sum of its proper divisors (15924184).

18121256 is a wasteful number, since it uses less digits than its factorization.

18121256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4544 (or 4540 counting only the distinct ones).

The product of its digits is 960, while the sum is 26.

The square root of 18121256 is about 4256.9068582716. The cubic root of 18121256 is about 262.6613055442.

The spelling of 18121256 in words is "eighteen million, one hundred twenty-one thousand, two hundred fifty-six".