18944397 has 6 divisors (see below), whose sum is σ = 27364142. Its totient is φ = 12629592.

The previous prime is 18944389. The next prime is 18944411. The reversal of 18944397 is 79344981.

It can be written as a sum of positive squares in only one way, i.e., 12257001 + 6687396 = 3501^2 + 2586^2 .

It is not a de Polignac number, because 18944397 - 2³ = 18944389 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 (18944327) 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, 1052458 + ... + 1052475.

Almost surely, 2^18944397 is an apocalyptic number.

It is an amenable number.

18944397 is a deficient number, since it is larger than the sum of its proper divisors (8419745).

18944397 is a wasteful number, since it uses less digits than its factorization.

18944397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2104939 (or 2104936 counting only the distinct ones).

The product of its digits is 217728, while the sum is 45.

The square root of 18944397 is about 4352.5161688384. The cubic root of 18944397 is about 266.5796102978.

The spelling of 18944397 in words is "eighteen million, nine hundred forty-four thousand, three hundred ninety-seven".