7878206304991 has 8 divisors (see below), whose sum is σ = 8890765736400. Its totient is φ = 6915040016640.

The previous prime is 7878206304961. The next prime is 7878206305001. The reversal of 7878206304991 is 1994036028787.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 7878206304991 - 2⁵ = 7878206304959 is a prime.

It is a super-2 number, since 2×7878206304991² (a number of 27 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 (7878206304961) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12348285426 + ... + 12348286063.

It is an arithmetic number, because the mean of its divisors is an integer number (1111345717050).

Almost surely, 2^{7878206304991} is an apocalyptic number.

7878206304991 is a deficient number, since it is larger than the sum of its proper divisors (1012559431409).

7878206304991 is a wasteful number, since it uses less digits than its factorization.

7878206304991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24696571529.

The product of its (nonzero) digits is 36578304, while the sum is 64.

The spelling of 7878206304991 in words is "seven trillion, eight hundred seventy-eight billion, two hundred six million, three hundred four thousand, nine hundred ninety-one".