12816418 has 4 divisors (see below), whose sum is σ = 19224630. Its totient is φ = 6408208.

The previous prime is 12816409. The next prime is 12816421. The reversal of 12816418 is 81461821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81461821 = 7 ⋅11637403.

It can be written as a sum of positive squares in only one way, i.e., 8543929 + 4272489 = 2923^2 + 2067^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 12816418.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3204103 + ... + 3204106.

Almost surely, 2^12816418 is an apocalyptic number.

12816418 is a deficient number, since it is larger than the sum of its proper divisors (6408212).

12816418 is an equidigital number, since it uses as much as digits as its factorization.

12816418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6408211.

The product of its digits is 3072, while the sum is 31.

The square root of 12816418 is about 3580.0025139656. The cubic root of 12816418 is about 234.0213899165.

The spelling of 12816418 in words is "twelve million, eight hundred sixteen thousand, four hundred eighteen".