2178435688651 has 48 divisors (see below), whose sum is σ = 2462182422336. Its totient is φ = 1920233889792.

The previous prime is 2178435688603. The next prime is 2178435688697. The reversal of 2178435688651 is 1568865348712.

It is not a de Polignac number, because 2178435688651 - 2²⁷ = 2178301470923 is a prime.

It is a super-2 number, since 2×2178435688651² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (2178435638651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 813758725 + ... + 813761401.

It is an arithmetic number, because the mean of its divisors is an integer number (51295467132).

Almost surely, 2^{2178435688651} is an apocalyptic number.

2178435688651 is a deficient number, since it is larger than the sum of its proper divisors (283746733685).

2178435688651 is a wasteful number, since it uses less digits than its factorization.

2178435688651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4196 (or 4177 counting only the distinct ones).

The product of its digits is 77414400, while the sum is 64.

The spelling of 2178435688651 in words is "two trillion, one hundred seventy-eight billion, four hundred thirty-five million, six hundred eighty-eight thousand, six hundred fifty-one".