78499477591 has 2 divisors, whose sum is σ = 78499477592. Its totient is φ = 78499477590.

The previous prime is 78499477561. The next prime is 78499477601. The reversal of 78499477591 is 19577499487.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78499477591 - 2⁹ = 78499477079 is a prime.

It is a super-2 number, since 2×78499477591² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78499477591.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78499477561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39249738795 + 39249738796.

It is an arithmetic number, because the mean of its divisors is an integer number (39249738796).

Almost surely, 2^78499477591 is an apocalyptic number.

78499477591 is a deficient number, since it is larger than the sum of its proper divisors (1).

78499477591 is an equidigital number, since it uses as much as digits as its factorization.

78499477591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 160030080, while the sum is 70.

The spelling of 78499477591 in words is "seventy-eight billion, four hundred ninety-nine million, four hundred seventy-seven thousand, five hundred ninety-one".