12991392 has 72 divisors (see below), whose sum is σ = 37477440. Its totient is φ = 4268160.

The previous prime is 12991379. The next prime is 12991393. The reversal of 12991392 is 29319921.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (12991393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22467 + ... + 23037.

It is an arithmetic number, because the mean of its divisors is an integer number (520520).

Almost surely, 2^12991392 is an apocalyptic number.

12991392 is a gapful number since it is divisible by the number (12) 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 12991392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18738720).

12991392 is an abundant number, since it is smaller than the sum of its proper divisors (24486048).

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

12991392 is a wasteful number, since it uses less digits than its factorization.

12991392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 666 (or 655 counting only the distinct ones).

The product of its digits is 8748, while the sum is 36.

The square root of 12991392 is about 3604.3573629705. The cubic root of 12991392 is about 235.0815591361.

The spelling of 12991392 in words is "twelve million, nine hundred ninety-one thousand, three hundred ninety-two".