12399321 has 16 divisors (see below), whose sum is σ = 18099648. Its totient is φ = 7488000.

The previous prime is 12399313. The next prime is 12399347.

It is a happy number.

12399321 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 12399321 - 2³ = 12399313 is a prime.

It is a super-2 number, since 2×12399321² = 307486322522082, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (12399301) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12765 + ... + 13701.

It is an arithmetic number, because the mean of its divisors is an integer number (1131228).

Almost surely, 2^12399321 is an apocalyptic number.

12399321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12399321 is a deficient number, since it is larger than the sum of its proper divisors (5700327).

12399321 is a wasteful number, since it uses less digits than its factorization.

12399321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1352.

The product of its digits is 2916, while the sum is 30.

The square root of 12399321 is about 3521.2669594906. The cubic root of 12399321 is about 231.4546806282.

It can be divided in two parts, 12399 and 321, that added together give a triangular number (12720 = T₁₅₉).

The spelling of 12399321 in words is "twelve million, three hundred ninety-nine thousand, three hundred twenty-one".