18990357 has 4 divisors (see below), whose sum is σ = 25320480. Its totient is φ = 12660236.

The previous prime is 18990353. The next prime is 18990359. The reversal of 18990357 is 75309981.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 18990357 - 2² = 18990353 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18990353) 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, 3165057 + ... + 3165062.

It is an arithmetic number, because the mean of its divisors is an integer number (6330120).

Almost surely, 2^18990357 is an apocalyptic number.

It is an amenable number.

18990357 is a deficient number, since it is larger than the sum of its proper divisors (6330123).

18990357 is an equidigital number, since it uses as much as digits as its factorization.

18990357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6330122.

The product of its (nonzero) digits is 68040, while the sum is 42.

The square root of 18990357 is about 4357.7926751969. The cubic root of 18990357 is about 266.7950144311.

The spelling of 18990357 in words is "eighteen million, nine hundred ninety thousand, three hundred fifty-seven".