18984478 has 16 divisors (see below), whose sum is σ = 30968784. Its totient is φ = 8691840.

The previous prime is 18984467. The next prime is 18984479. The reversal of 18984478 is 87448981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18984479) 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, 6288 + ... + 8803.

It is an arithmetic number, because the mean of its divisors is an integer number (1935549).

Almost surely, 2^18984478 is an apocalyptic number.

18984478 is a deficient number, since it is larger than the sum of its proper divisors (11984306).

18984478 is a wasteful number, since it uses less digits than its factorization.

18984478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15147.

The product of its digits is 516096, while the sum is 49.

The square root of 18984478 is about 4357.1180842387. The cubic root of 18984478 is about 266.7674802853.

The spelling of 18984478 in words is "eighteen million, nine hundred eighty-four thousand, four hundred seventy-eight".