18781025 has 18 divisors (see below), whose sum is σ = 24590502. Its totient is φ = 14227200.

The previous prime is 18781013. The next prime is 18781033. The reversal of 18781025 is 52018781.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 667489 + 18113536 = 817^2 + 4256^2 .

It is not a de Polignac number, because 18781025 - 2¹⁰ = 18780001 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18780982 and 18781000.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 7985 + ... + 10065.

It is an arithmetic number, because the mean of its divisors is an integer number (1366139).

Almost surely, 2^18781025 is an apocalyptic number.

It is an amenable number.

18781025 is a deficient number, since it is larger than the sum of its proper divisors (5809477).

18781025 is a wasteful number, since it uses less digits than its factorization.

18781025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2129 (or 2105 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 32.

The square root of 18781025 is about 4333.7079966237. The cubic root of 18781025 is about 265.8110903605.

The spelling of 18781025 in words is "eighteen million, seven hundred eighty-one thousand, twenty-five".