3216991 has 2 divisors, whose sum is σ = 3216992. Its totient is φ = 3216990.

The previous prime is 3216979. The next prime is 3217001. The reversal of 3216991 is 1996123.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3216991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3216911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1608495 + 1608496.

It is an arithmetic number, because the mean of its divisors is an integer number (1608496).

Almost surely, 2^3216991 is an apocalyptic number.

3216991 is a deficient number, since it is larger than the sum of its proper divisors (1).

3216991 is an equidigital number, since it uses as much as digits as its factorization.

3216991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2916, while the sum is 31.

The square root of 3216991 is about 1793.5972234590. The cubic root of 3216991 is about 147.6216137687.

The spelling of 3216991 in words is "three million, two hundred sixteen thousand, nine hundred ninety-one".