3191249891 has 2 divisors, whose sum is σ = 3191249892. Its totient is φ = 3191249890.

The previous prime is 3191249857. The next prime is 3191249921. The reversal of 3191249891 is 1989421913.

It is a strong prime.

It is an emirp because it is prime and its reverse (1989421913) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3191249891 - 2¹⁸ = 3190987747 is a prime.

It is not a weakly prime, because it can be changed into another prime (3191249491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1595624945 + 1595624946.

It is an arithmetic number, because the mean of its divisors is an integer number (1595624946).

Almost surely, 2^3191249891 is an apocalyptic number.

3191249891 is a deficient number, since it is larger than the sum of its proper divisors (1).

3191249891 is an equidigital number, since it uses as much as digits as its factorization.

3191249891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 47.

The square root of 3191249891 is about 56491.1487845662. The cubic root of 3191249891 is about 1472.2682201340.

The spelling of 3191249891 in words is "three billion, one hundred ninety-one million, two hundred forty-nine thousand, eight hundred ninety-one".