18943397 has 12 divisors (see below), whose sum is σ = 21271488. Its totient is φ = 16849800.

The previous prime is 18943381. The next prime is 18943417. The reversal of 18943397 is 79334981.

It is a happy number.

It is not a de Polignac number, because 18943397 - 2⁴ = 18943381 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 (18943357) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4022 + ... + 7352.

It is an arithmetic number, because the mean of its divisors is an integer number (1772624).

Almost surely, 2^18943397 is an apocalyptic number.

It is an amenable number.

18943397 is a deficient number, since it is larger than the sum of its proper divisors (2328091).

18943397 is a wasteful number, since it uses less digits than its factorization.

18943397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3400 (or 3389 counting only the distinct ones).

The product of its digits is 163296, while the sum is 44.

The square root of 18943397 is about 4352.4012912414. The cubic root of 18943397 is about 266.5749196532.

The spelling of 18943397 in words is "eighteen million, nine hundred forty-three thousand, three hundred ninety-seven".