18930947 has 4 divisors (see below), whose sum is σ = 21635376. Its totient is φ = 16226520.

The previous prime is 18930931. The next prime is 18930949. The reversal of 18930947 is 74903981.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74903981 = 59 ⋅1269559.

It is a cyclic number.

It is not a de Polignac number, because 18930947 - 2⁴ = 18930931 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18930949) 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, 1352204 + ... + 1352217.

It is an arithmetic number, because the mean of its divisors is an integer number (5408844).

Almost surely, 2^18930947 is an apocalyptic number.

18930947 is a deficient number, since it is larger than the sum of its proper divisors (2704429).

18930947 is an equidigital number, since it uses as much as digits as its factorization.

18930947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2704428.

The product of its (nonzero) digits is 54432, while the sum is 41.

The square root of 18930947 is about 4350.9708112098. The cubic root of 18930947 is about 266.5165073018.

The spelling of 18930947 in words is "eighteen million, nine hundred thirty thousand, nine hundred forty-seven".