18250993 has 4 divisors (see below), whose sum is σ = 18639360. Its totient is φ = 17862628.

The previous prime is 18250957. The next prime is 18251021. The reversal of 18250993 is 39905281.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 39905281 = 13 ⋅3069637.

It is a cyclic number.

It is not a de Polignac number, because 18250993 - 2⁹ = 18250481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18250093) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 194113 + ... + 194206.

It is an arithmetic number, because the mean of its divisors is an integer number (4659840).

Almost surely, 2^18250993 is an apocalyptic number.

It is an amenable number.

18250993 is a deficient number, since it is larger than the sum of its proper divisors (388367).

18250993 is an equidigital number, since it uses as much as digits as its factorization.

18250993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388366.

The product of its (nonzero) digits is 19440, while the sum is 37.

The square root of 18250993 is about 4272.1180929370. The cubic root of 18250993 is about 263.2866464617.

The spelling of 18250993 in words is "eighteen million, two hundred fifty thousand, nine hundred ninety-three".