18994564334 has 4 divisors (see below), whose sum is σ = 28491846504. Its totient is φ = 9497282166.

The previous prime is 18994564331. The next prime is 18994564357. The reversal of 18994564334 is 43346549981.

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

It is a self number, because there is not a number n which added to its sum of digits gives 18994564334.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18994564331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4748641082 + ... + 4748641085.

It is an arithmetic number, because the mean of its divisors is an integer number (7122961626).

Almost surely, 2^18994564334 is an apocalyptic number.

18994564334 is a deficient number, since it is larger than the sum of its proper divisors (9497282170).

18994564334 is an equidigital number, since it uses as much as digits as its factorization.

18994564334 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9497282169.

The product of its digits is 11197440, while the sum is 56.

The spelling of 18994564334 in words is "eighteen billion, nine hundred ninety-four million, five hundred sixty-four thousand, three hundred thirty-four".