18994038 has 16 divisors (see below), whose sum is σ = 43415040. Its totient is φ = 5426856.

The previous prime is 18994037. The next prime is 18994039. The reversal of 18994038 is 83049981.

It is an interprime number because it is at equal distance from previous prime (18994037) and next prime (18994039).

It is a Harshad number since it is a multiple of its sum of digits (42), and also a Moran number because the ratio is a prime number: 452239 = 18994038 / (1 + 8 + 9 + 9 + 4 + 0 + 3 + 8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18994033) 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 7 ways as a sum of consecutive naturals, for example, 226078 + ... + 226161.

It is an arithmetic number, because the mean of its divisors is an integer number (2713440).

Almost surely, 2^18994038 is an apocalyptic number.

18994038 is an abundant number, since it is smaller than the sum of its proper divisors (24421002).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18994038 is a wasteful number, since it uses less digits than its factorization.

18994038 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 452251.

The product of its (nonzero) digits is 62208, while the sum is 42.

The square root of 18994038 is about 4358.2150015803. The cubic root of 18994038 is about 266.8122514074.

The spelling of 18994038 in words is "eighteen million, nine hundred ninety-four thousand, thirty-eight".