78807256571 has 4 divisors (see below), whose sum is σ = 80639983512. Its totient is φ = 76974529632.

The previous prime is 78807256547. The next prime is 78807256573. The reversal of 78807256571 is 17565270887.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78807256571 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78807256573) 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, 916363406 + ... + 916363491.

It is an arithmetic number, because the mean of its divisors is an integer number (20159995878).

Almost surely, 2^78807256571 is an apocalyptic number.

78807256571 is a deficient number, since it is larger than the sum of its proper divisors (1832726941).

78807256571 is a wasteful number, since it uses less digits than its factorization.

78807256571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1832726940.

The product of its (nonzero) digits is 6585600, while the sum is 56.

The spelling of 78807256571 in words is "seventy-eight billion, eight hundred seven million, two hundred fifty-six thousand, five hundred seventy-one".