78320771933 has 4 divisors (see below), whose sum is σ = 78322051548. Its totient is φ = 78319492320.

The previous prime is 78320771923. The next prime is 78320771939. The reversal of 78320771933 is 33917702387.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 33917702387 = 11159 ⋅3039493.

It can be written as a sum of positive squares in 2 ways, for example, as 23244661444 + 55076110489 = 152462^2 + 234683^2 .

It is a cyclic number.

It is not a de Polignac number, because 78320771933 - 2⁶ = 78320771869 is a prime.

It is a super-2 number, since 2×78320771933² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78320771939) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 543128 + ... + 672033.

It is an arithmetic number, because the mean of its divisors is an integer number (19580512887).

Almost surely, 2^78320771933 is an apocalyptic number.

It is an amenable number.

78320771933 is a deficient number, since it is larger than the sum of its proper divisors (1279615).

78320771933 is a wasteful number, since it uses less digits than its factorization.

78320771933 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1279614.

The product of its (nonzero) digits is 1333584, while the sum is 50.

The spelling of 78320771933 in words is "seventy-eight billion, three hundred twenty million, seven hundred seventy-one thousand, nine hundred thirty-three".