79923543991 has 2 divisors, whose sum is σ = 79923543992. Its totient is φ = 79923543990.

The previous prime is 79923543977. The next prime is 79923544073. The reversal of 79923543991 is 19934532997.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 79923543991 - 2¹⁵ = 79923511223 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79923543941) 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, 39961771995 + 39961771996.

It is an arithmetic number, because the mean of its divisors is an integer number (39961771996).

Almost surely, 2^79923543991 is an apocalyptic number.

79923543991 is a deficient number, since it is larger than the sum of its proper divisors (1).

79923543991 is an equidigital number, since it uses as much as digits as its factorization.

79923543991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16533720, while the sum is 61.

The spelling of 79923543991 in words is "seventy-nine billion, nine hundred twenty-three million, five hundred forty-three thousand, nine hundred ninety-one".