3156991 has 2 divisors, whose sum is σ = 3156992. Its totient is φ = 3156990.

The previous prime is 3156977. The next prime is 3156997. The reversal of 3156991 is 1996513.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3156991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3156997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1578495 + 1578496.

It is an arithmetic number, because the mean of its divisors is an integer number (1578496).

Almost surely, 2^3156991 is an apocalyptic number.

3156991 is a deficient number, since it is larger than the sum of its proper divisors (1).

3156991 is an equidigital number, since it uses as much as digits as its factorization.

3156991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7290, while the sum is 34.

The square root of 3156991 is about 1776.7923345175. The cubic root of 3156991 is about 146.6980861292.

The spelling of 3156991 in words is "three million, one hundred fifty-six thousand, nine hundred ninety-one".