78771257845 has 32 divisors (see below), whose sum is σ = 108902481408. Its totient is φ = 53578533888.

The previous prime is 78771257839. The next prime is 78771257869. The reversal of 78771257845 is 54875217787.

It is a cyclic number.

It is not a de Polignac number, because 78771257845 - 2³ = 78771257837 is a prime.

It is a super-2 number, since 2×78771257845² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6932689 + ... + 6944041.

It is an arithmetic number, because the mean of its divisors is an integer number (3403202544).

Almost surely, 2^78771257845 is an apocalyptic number.

It is an amenable number.

78771257845 is a deficient number, since it is larger than the sum of its proper divisors (30131223563).

78771257845 is a wasteful number, since it uses less digits than its factorization.

78771257845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12949.

The product of its digits is 30732800, while the sum is 61.

The spelling of 78771257845 in words is "seventy-eight billion, seven hundred seventy-one million, two hundred fifty-seven thousand, eight hundred forty-five".