78894136161 has 63 divisors (see below), whose sum is σ = 120641010627. Its totient is φ = 51569751600.

The previous prime is 78894136151. The next prime is 78894136177. The reversal of 78894136161 is 16163149887.

The square root of 78894136161 is 280881.

It is a perfect power (a square), and thus also a powerful number.

78894136161 is a `hidden beast` number, since 7 + 8 + 8 + 9 + 4 + 13 + 616 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 75800551761 + 3093584400 = 275319^2 + 55620^2 .

It is a de Polignac number, because none of the positive numbers 2^k-78894136161 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 78894136098 and 78894136107.

It is not an unprimeable number, because it can be changed into a prime (78894136151) by changing a digit.

It is a polite number, since it can be written in 62 ways as a sum of consecutive naturals, for example, 765962436 + ... + 765962538.

Almost surely, 2^78894136161 is an apocalyptic number.

78894136161 is the 280881-st square number.

78894136161 is the 140441-st centered octagonal number.

It is an amenable number.

78894136161 is a deficient number, since it is larger than the sum of its proper divisors (41746874466).

78894136161 is an frugal number, since it uses more digits than its factorization.

78894136161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 426 (or 207 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 54.

The spelling of 78894136161 in words is "seventy-eight billion, eight hundred ninety-four million, one hundred thirty-six thousand, one hundred sixty-one".