18687425 has 6 divisors (see below), whose sum is σ = 23172438. Its totient is φ = 14949920.

The previous prime is 18687407. The next prime is 18687433. The reversal of 18687425 is 52478681.

18687425 is nontrivially palindromic in base 8.

It can be written as a sum of positive squares in 3 ways, for example, as 16384 + 18671041 = 128^2 + 4321^2 .

It is not a de Polignac number, because 18687425 - 2⁸ = 18687169 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 373724 + ... + 373773.

It is an arithmetic number, because the mean of its divisors is an integer number (3862073).

Almost surely, 2^18687425 is an apocalyptic number.

It is an amenable number.

18687425 is a deficient number, since it is larger than the sum of its proper divisors (4485013).

18687425 is an equidigital number, since it uses as much as digits as its factorization.

18687425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 747507 (or 747502 counting only the distinct ones).

The product of its digits is 107520, while the sum is 41.

The square root of 18687425 is about 4322.8954417150. The cubic root of 18687425 is about 265.3687757607.

The spelling of 18687425 in words is "eighteen million, six hundred eighty-seven thousand, four hundred twenty-five".