6451087991 has 2 divisors, whose sum is σ = 6451087992. Its totient is φ = 6451087990.

The previous prime is 6451087967. The next prime is 6451087997. The reversal of 6451087991 is 1997801546.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6451087991 - 2⁶ = 6451087927 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6451087997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3225543995 + 3225543996.

It is an arithmetic number, because the mean of its divisors is an integer number (3225543996).

Almost surely, 2^6451087991 is an apocalyptic number.

6451087991 is a deficient number, since it is larger than the sum of its proper divisors (1).

6451087991 is an equidigital number, since it uses as much as digits as its factorization.

6451087991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 544320, while the sum is 50.

The square root of 6451087991 is about 80318.6652715295. The cubic root of 6451087991 is about 1861.5626432381.

The spelling of 6451087991 in words is "six billion, four hundred fifty-one million, eighty-seven thousand, nine hundred ninety-one".