18990723 has 8 divisors (see below), whose sum is σ = 25369936. Its totient is φ = 12636000.

The previous prime is 18990721. The next prime is 18990761. The reversal of 18990723 is 32709981.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18990723 - 2¹ = 18990721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18990721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4228 + ... + 7473.

It is an arithmetic number, because the mean of its divisors is an integer number (3171242).

Almost surely, 2^18990723 is an apocalyptic number.

18990723 is a deficient number, since it is larger than the sum of its proper divisors (6379213).

18990723 is a wasteful number, since it uses less digits than its factorization.

18990723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12245.

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 18990723 is about 4357.8346687317. The cubic root of 18990723 is about 266.7967283948.

The spelling of 18990723 in words is "eighteen million, nine hundred ninety thousand, seven hundred twenty-three".