18601994 has 4 divisors (see below), whose sum is σ = 27902994. Its totient is φ = 9300996.

The previous prime is 18601967. The next prime is 18602027. The reversal of 18601994 is 49910681.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 49910681 = 2729 ⋅18289.

It can be written as a sum of positive squares in only one way, i.e., 18601969 + 25 = 4313^2 + 5^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4650497 + ... + 4650500.

Almost surely, 2^18601994 is an apocalyptic number.

18601994 is a deficient number, since it is larger than the sum of its proper divisors (9301000).

18601994 is an equidigital number, since it uses as much as digits as its factorization.

18601994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9300999.

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 18601994 is about 4313.0028982137. The cubic root of 18601994 is about 264.9637733794.

The spelling of 18601994 in words is "eighteen million, six hundred one thousand, nine hundred ninety-four".