18678725 has 18 divisors (see below), whose sum is σ = 25086006. Its totient is φ = 13790400.

The previous prime is 18678719. The next prime is 18678731. The reversal of 18678725 is 52787681.

It is an interprime number because it is at equal distance from previous prime (18678719) and next prime (18678731).

It can be written as a sum of positive squares in 9 ways, for example, as 8579041 + 10099684 = 2929^2 + 3178^2 .

It is not a de Polignac number, because 18678725 - 2¹⁸ = 18416581 is a prime.

It is a Duffinian number.

It is a congruent 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 17 ways as a sum of consecutive naturals, for example, 2015 + ... + 6435.

It is an arithmetic number, because the mean of its divisors is an integer number (1393667).

Almost surely, 2^18678725 is an apocalyptic number.

It is an amenable number.

18678725 is a deficient number, since it is larger than the sum of its proper divisors (6407281).

18678725 is a wasteful number, since it uses less digits than its factorization.

18678725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4457 (or 4439 counting only the distinct ones).

The product of its digits is 188160, while the sum is 44.

The square root of 18678725 is about 4321.8890545686. The cubic root of 18678725 is about 265.3275882292.

The spelling of 18678725 in words is "eighteen million, six hundred seventy-eight thousand, seven hundred twenty-five".