12717991 has 8 divisors (see below), whose sum is σ = 14941584. Its totient is φ = 10672320.

The previous prime is 12717983. The next prime is 12718003. The reversal of 12717991 is 19971721.

12717991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 12717991 - 2³ = 12717983 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12717991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12717941) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44326 + ... + 44611.

It is an arithmetic number, because the mean of its divisors is an integer number (1867698).

Almost surely, 2^12717991 is an apocalyptic number.

12717991 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

12717991 is a deficient number, since it is larger than the sum of its proper divisors (2223593).

12717991 is a wasteful number, since it uses less digits than its factorization.

12717991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88961.

The product of its digits is 7938, while the sum is 37.

The square root of 12717991 is about 3566.2292410892. The cubic root of 12717991 is about 233.4207738040.

The spelling of 12717991 in words is "twelve million, seven hundred seventeen thousand, nine hundred ninety-one".