7991632081 has 2 divisors, whose sum is σ = 7991632082. Its totient is φ = 7991632080.

The previous prime is 7991632067. The next prime is 7991632111. The reversal of 7991632081 is 1802361997.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4649057856 + 3342574225 = 68184^2 + 57815^2 .

It is a cyclic number.

It is not a de Polignac number, because 7991632081 - 2⁷ = 7991631953 is a prime.

It is a super-2 number, since 2×7991632081² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (7991632681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3995816040 + 3995816041.

It is an arithmetic number, because the mean of its divisors is an integer number (3995816041).

Almost surely, 2^7991632081 is an apocalyptic number.

It is an amenable number.

7991632081 is a deficient number, since it is larger than the sum of its proper divisors (1).

7991632081 is an equidigital number, since it uses as much as digits as its factorization.

7991632081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 163296, while the sum is 46.

The square root of 7991632081 is about 89395.9287719525. The cubic root of 7991632081 is about 1999.3024301431.

The spelling of 7991632081 in words is "seven billion, nine hundred ninety-one million, six hundred thirty-two thousand, eighty-one".