12391400 has 96 divisors (see below), whose sum is σ = 33747840. Its totient is φ = 4143360.

The previous prime is 12391399. The next prime is 12391403. The reversal of 12391400 is 419321.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (12391403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 74117 + ... + 74283.

It is an arithmetic number, because the mean of its divisors is an integer number (351540).

Almost surely, 2^12391400 is an apocalyptic number.

12391400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12391400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16873920).

12391400 is an abundant number, since it is smaller than the sum of its proper divisors (21356440).

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

12391400 is a wasteful number, since it uses less digits than its factorization.

12391400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243 (or 234 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 12391400 is about 3520.1420425886. The cubic root of 12391400 is about 231.4053837605.

The spelling of 12391400 in words is "twelve million, three hundred ninety-one thousand, four hundred".