12991870 has 8 divisors (see below), whose sum is σ = 23385384. Its totient is φ = 5196744.

The previous prime is 12991813. The next prime is 12991871. The reversal of 12991870 is 7819921.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12991871) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 649584 + ... + 649603.

It is an arithmetic number, because the mean of its divisors is an integer number (2923173).

Almost surely, 2^12991870 is an apocalyptic number.

12991870 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

12991870 is a deficient number, since it is larger than the sum of its proper divisors (10393514).

12991870 is a wasteful number, since it uses less digits than its factorization.

12991870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1299194.

The product of its (nonzero) digits is 9072, while the sum is 37.

The square root of 12991870 is about 3604.4236709910. The cubic root of 12991870 is about 235.0844422659.

It can be divided in two parts, 12991 and 870, that added together give a triangular number (13861 = T₁₆₆).

The spelling of 12991870 in words is "twelve million, nine hundred ninety-one thousand, eight hundred seventy".