18416393 has 4 divisors (see below), whose sum is σ = 18424980. Its totient is φ = 18407808.

The previous prime is 18416383. The next prime is 18416407. The reversal of 18416393 is 39361481.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 39361481 = 1361 ⋅28921.

It can be written as a sum of positive squares in 2 ways, for example, as 9193024 + 9223369 = 3032^2 + 3037^2 .

It is a cyclic number.

It is not a de Polignac number, because 18416393 - 2⁶ = 18416329 is a prime.

It is a super-2 number, since 2×18416393² = 678327062260898, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18416383) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1973 + ... + 6381.

It is an arithmetic number, because the mean of its divisors is an integer number (4606245).

Almost surely, 2^18416393 is an apocalyptic number.

It is an amenable number.

18416393 is a deficient number, since it is larger than the sum of its proper divisors (8587).

18416393 is an equidigital number, since it uses as much as digits as its factorization.

18416393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8586.

The product of its digits is 15552, while the sum is 35.

The square root of 18416393 is about 4291.4325114115. The cubic root of 18416393 is about 264.0796027553.

The spelling of 18416393 in words is "eighteen million, four hundred sixteen thousand, three hundred ninety-three".