3121696691 has 2 divisors, whose sum is σ = 3121696692. Its totient is φ = 3121696690.

The previous prime is 3121696687. The next prime is 3121696693. The reversal of 3121696691 is 1966961213.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 3121696691 - 2² = 3121696687 is a prime.

Together with 3121696693, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (3121696693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1560848345 + 1560848346.

It is an arithmetic number, because the mean of its divisors is an integer number (1560848346).

Almost surely, 2^3121696691 is an apocalyptic number.

3121696691 is a deficient number, since it is larger than the sum of its proper divisors (1).

3121696691 is an equidigital number, since it uses as much as digits as its factorization.

3121696691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 104976, while the sum is 44.

The square root of 3121696691 is about 55872.1459315820. The cubic root of 3121696691 is about 1461.4935443350.

The spelling of 3121696691 in words is "three billion, one hundred twenty-one million, six hundred ninety-six thousand, six hundred ninety-one".