78823271702561 has 4 divisors (see below), whose sum is σ = 78823406726400. Its totient is φ = 78823136678724.

The previous prime is 78823271702507. The next prime is 78823271702569. The reversal of 78823271702561 is 16520717232887.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78823271702561 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78823271702561.

It is not an unprimeable number, because it can be changed into a prime (78823271702569) 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, 66632441 + ... + 67805078.

It is an arithmetic number, because the mean of its divisors is an integer number (19705851681600).

Almost surely, 2^{78823271702561} is an apocalyptic number.

It is an amenable number.

78823271702561 is a deficient number, since it is larger than the sum of its proper divisors (135023839).

78823271702561 is a wasteful number, since it uses less digits than its factorization.

78823271702561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135023838.

The product of its (nonzero) digits is 15805440, while the sum is 59.

The spelling of 78823271702561 in words is "seventy-eight trillion, eight hundred twenty-three billion, two hundred seventy-one million, seven hundred two thousand, five hundred sixty-one".