18125681 has 16 divisors (see below), whose sum is σ = 21312000. Its totient is φ = 15095808.

The previous prime is 18125659. The next prime is 18125687. The reversal of 18125681 is 18652181.

It is not a de Polignac number, because 18125681 - 2⁶ = 18125617 is a prime.

It is a super-2 number, since 2×18125681² = 657080623427522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18125687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40145 + ... + 40593.

It is an arithmetic number, because the mean of its divisors is an integer number (1332000).

Almost surely, 2^18125681 is an apocalyptic number.

It is an amenable number.

18125681 is a deficient number, since it is larger than the sum of its proper divisors (3186319).

18125681 is an equidigital number, since it uses as much as digits as its factorization.

18125681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 608.

The product of its digits is 3840, while the sum is 32.

The square root of 18125681 is about 4257.4265701243. The cubic root of 18125681 is about 262.6826834164.

The spelling of 18125681 in words is "eighteen million, one hundred twenty-five thousand, six hundred eighty-one".