18945973 has 6 divisors (see below), whose sum is σ = 20126306. Its totient is φ = 17831232.

The previous prime is 18945967. The next prime is 18946003. The reversal of 18945973 is 37954981.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 9746884 + 9199089 = 3122^2 + 3033^2 .

It is not a de Polignac number, because 18945973 - 2⁹ = 18945461 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18946973) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 32490 + ... + 33067.

Almost surely, 2^18945973 is an apocalyptic number.

It is an amenable number.

18945973 is a deficient number, since it is larger than the sum of its proper divisors (1180333).

18945973 is an equidigital number, since it uses as much as digits as its factorization.

18945973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65591 (or 65574 counting only the distinct ones).

The product of its digits is 272160, while the sum is 46.

The square root of 18945973 is about 4352.6972097769. The cubic root of 18945973 is about 266.5870024187.

The spelling of 18945973 in words is "eighteen million, nine hundred forty-five thousand, nine hundred seventy-three".