87997167991 has 2 divisors, whose sum is σ = 87997167992. Its totient is φ = 87997167990.

The previous prime is 87997167977. The next prime is 87997167997. The reversal of 87997167991 is 19976179978.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-87997167991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87997167997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43998583995 + 43998583996.

It is an arithmetic number, because the mean of its divisors is an integer number (43998583996).

Almost surely, 2^87997167991 is an apocalyptic number.

87997167991 is a deficient number, since it is larger than the sum of its proper divisors (1).

87997167991 is an equidigital number, since it uses as much as digits as its factorization.

87997167991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108020304, while the sum is 73.

The spelling of 87997167991 in words is "eighty-seven billion, nine hundred ninety-seven million, one hundred sixty-seven thousand, nine hundred ninety-one".