18251966 has 4 divisors (see below), whose sum is σ = 27377952. Its totient is φ = 9125982.

The previous prime is 18251957. The next prime is 18251977. The reversal of 18251966 is 66915281.

It is a semiprime because it is the product of two primes.

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 as a sum of consecutive naturals, namely, 4562990 + ... + 4562993.

It is an arithmetic number, because the mean of its divisors is an integer number (6844488).

Almost surely, 2^18251966 is an apocalyptic number.

18251966 is a deficient number, since it is larger than the sum of its proper divisors (9125986).

18251966 is an equidigital number, since it uses as much as digits as its factorization.

18251966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9125985.

The product of its digits is 25920, while the sum is 38.

The square root of 18251966 is about 4272.2319693575. The cubic root of 18251966 is about 263.2913251725.

The spelling of 18251966 in words is "eighteen million, two hundred fifty-one thousand, nine hundred sixty-six".