12991800 has 96 divisors (see below), whose sum is σ = 41068800. Its totient is φ = 3396480.

The previous prime is 12991799. The next prime is 12991807. The reversal of 12991800 is 819921.

12991800 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12991807) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35217 + ... + 35583.

It is an arithmetic number, because the mean of its divisors is an integer number (427800).

Almost surely, 2^12991800 is an apocalyptic number.

12991800 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 12991800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20534400).

12991800 is an abundant number, since it is smaller than the sum of its proper divisors (28077000).

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

12991800 is a wasteful number, since it uses less digits than its factorization.

12991800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 445 (or 436 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 30.

The square root of 12991800 is about 3604.4139606876. The cubic root of 12991800 is about 235.0840200546.

The spelling of 12991800 in words is "twelve million, nine hundred ninety-one thousand, eight hundred".