1296386691 has 4 divisors (see below), whose sum is σ = 1728515592. Its totient is φ = 864257792.

The previous prime is 1296386683. The next prime is 1296386717. The reversal of 1296386691 is 1966836921.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1296386691 - 2³ = 1296386683 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1296387691) 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 3 ways as a sum of consecutive naturals, for example, 216064446 + ... + 216064451.

It is an arithmetic number, because the mean of its divisors is an integer number (432128898).

Almost surely, 2^1296386691 is an apocalyptic number.

1296386691 is a deficient number, since it is larger than the sum of its proper divisors (432128901).

1296386691 is an equidigital number, since it uses as much as digits as its factorization.

1296386691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 432128900.

The product of its digits is 839808, while the sum is 51.

The square root of 1296386691 is about 36005.3703077749. The cubic root of 1296386691 is about 1090.3807807464.

The spelling of 1296386691 in words is "one billion, two hundred ninety-six million, three hundred eighty-six thousand, six hundred ninety-one".