78982561 has 24 divisors (see below), whose sum is σ = 99173160. Its totient is φ = 62479872.

The previous prime is 78982559. The next prime is 78982567. The reversal of 78982561 is 16528987.

It can be written as a sum of positive squares in 4 ways, for example, as 50680161 + 28302400 = 7119^2 + 5320^2 .

It is not a de Polignac number, because 78982561 - 2¹ = 78982559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78982567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43255 + ... + 45043.

It is an arithmetic number, because the mean of its divisors is an integer number (4132215).

Almost surely, 2^78982561 is an apocalyptic number.

It is an amenable number.

78982561 is a deficient number, since it is larger than the sum of its proper divisors (20190599).

78982561 is a wasteful number, since it uses less digits than its factorization.

78982561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1873 (or 1866 counting only the distinct ones).

The product of its digits is 241920, while the sum is 46.

The square root of 78982561 is about 8887.2133427751. The cubic root of 78982561 is about 429.0524673976.

The spelling of 78982561 in words is "seventy-eight million, nine hundred eighty-two thousand, five hundred sixty-one".