3215551991 has 2 divisors, whose sum is σ = 3215551992. Its totient is φ = 3215551990.

The previous prime is 3215551967. The next prime is 3215552017. The reversal of 3215551991 is 1991555123.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 3215551991 - 2¹⁰ = 3215550967 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3215551091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1607775995 + 1607775996.

It is an arithmetic number, because the mean of its divisors is an integer number (1607775996).

Almost surely, 2^3215551991 is an apocalyptic number.

3215551991 is a deficient number, since it is larger than the sum of its proper divisors (1).

3215551991 is an equidigital number, since it uses as much as digits as its factorization.

3215551991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 60750, while the sum is 41.

The square root of 3215551991 is about 56705.8373626561. The cubic root of 3215551991 is about 1475.9959935494.

The spelling of 3215551991 in words is "three billion, two hundred fifteen million, five hundred fifty-one thousand, nine hundred ninety-one".