18978703 has 4 divisors (see below), whose sum is σ = 19803888. Its totient is φ = 18153520.

The previous prime is 18978691. The next prime is 18978709. The reversal of 18978703 is 30787981.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18978703 - 2⁹ = 18978191 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18978703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18978709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 412558 + ... + 412603.

It is an arithmetic number, because the mean of its divisors is an integer number (4950972).

Almost surely, 2^18978703 is an apocalyptic number.

18978703 is a deficient number, since it is larger than the sum of its proper divisors (825185).

18978703 is an equidigital number, since it uses as much as digits as its factorization.

18978703 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 825184.

The product of its (nonzero) digits is 84672, while the sum is 43.

The square root of 18978703 is about 4356.4553251468. The cubic root of 18978703 is about 266.7404276858.

The spelling of 18978703 in words is "eighteen million, nine hundred seventy-eight thousand, seven hundred three".