12320406 has 48 divisors (see below), whose sum is σ = 30704544. Its totient is φ = 3497472.

The previous prime is 12320401. The next prime is 12320411. The reversal of 12320406 is 60402321.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (12320401) and next prime (12320411).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12320401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 34726 + ... + 35078.

It is an arithmetic number, because the mean of its divisors is an integer number (639678).

Almost surely, 2^12320406 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12320406, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15352272).

12320406 is an abundant number, since it is smaller than the sum of its proper divisors (18384138).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12320406 is a wasteful number, since it uses less digits than its factorization.

12320406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 645 (or 642 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 12320406 is about 3510.0435894729. The cubic root of 12320406 is about 230.9626070918.

Adding to 12320406 its reverse (60402321), we get a palindrome (72722727).

The spelling of 12320406 in words is "twelve million, three hundred twenty thousand, four hundred six".