7987698991 has 2 divisors, whose sum is σ = 7987698992. Its totient is φ = 7987698990.

The previous prime is 7987698967. The next prime is 7987699081. The reversal of 7987698991 is 1998967897.

It is a weak prime.

It is an emirp because it is prime and its reverse (1998967897) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7987698991 - 2⁵ = 7987698959 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7987698941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3993849495 + 3993849496.

It is an arithmetic number, because the mean of its divisors is an integer number (3993849496).

Almost surely, 2^7987698991 is an apocalyptic number.

7987698991 is a deficient number, since it is larger than the sum of its proper divisors (1).

7987698991 is an equidigital number, since it uses as much as digits as its factorization.

7987698991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 123451776, while the sum is 73.

The square root of 7987698991 is about 89373.9279152483. The cubic root of 7987698991 is about 1998.9743900687.

The spelling of 7987698991 in words is "seven billion, nine hundred eighty-seven million, six hundred ninety-eight thousand, nine hundred ninety-one".