18997736 has 8 divisors (see below), whose sum is σ = 35620770. Its totient is φ = 9498864.

The previous prime is 18997733. The next prime is 18997757. The reversal of 18997736 is 63779981.

It can be written as a sum of positive squares in only one way, i.e., 9572836 + 9424900 = 3094^2 + 3070^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (18997733) by changing a digit.

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, 1187351 + ... + 1187366.

Almost surely, 2^18997736 is an apocalyptic number.

It is an amenable number.

18997736 is a deficient number, since it is larger than the sum of its proper divisors (16623034).

18997736 is a wasteful number, since it uses less digits than its factorization.

18997736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2374723 (or 2374719 counting only the distinct ones).

The product of its digits is 571536, while the sum is 50.

The square root of 18997736 is about 4358.6392371932. The cubic root of 18997736 is about 266.8295657471.

The spelling of 18997736 in words is "eighteen million, nine hundred ninety-seven thousand, seven hundred thirty-six".