18994273 has 2 divisors, whose sum is σ = 18994274. Its totient is φ = 18994272.

The previous prime is 18994201. The next prime is 18994277. The reversal of 18994273 is 37249981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10036224 + 8958049 = 3168^2 + 2993^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18994273 is a prime.

It is not a weakly prime, because it can be changed into another prime (18994277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9497136 + 9497137.

It is an arithmetic number, because the mean of its divisors is an integer number (9497137).

Almost surely, 2^18994273 is an apocalyptic number.

It is an amenable number.

18994273 is a deficient number, since it is larger than the sum of its proper divisors (1).

18994273 is an equidigital number, since it uses as much as digits as its factorization.

18994273 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108864, while the sum is 43.

The square root of 18994273 is about 4358.2419620760. The cubic root of 18994273 is about 266.8133517635.

The spelling of 18994273 in words is "eighteen million, nine hundred ninety-four thousand, two hundred seventy-three".