78861582 has 72 divisors (see below), whose sum is σ = 182171808. Its totient is φ = 24641280.

The previous prime is 78861577. The next prime is 78861599. The reversal of 78861582 is 28516887.

78861582 is a `hidden beast` number, since 7 + 8 + 8 + 61 + 582 = 666.

It is a congruent number.

It is an unprimeable number.

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 35 ways as a sum of consecutive naturals, for example, 812958 + ... + 813054.

It is an arithmetic number, because the mean of its divisors is an integer number (2530164).

Almost surely, 2^78861582 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78861582, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91085904).

78861582 is an abundant number, since it is smaller than the sum of its proper divisors (103310226).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78861582 is a wasteful number, since it uses less digits than its factorization.

78861582 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214 (or 180 counting only the distinct ones).

The product of its digits is 215040, while the sum is 45.

The square root of 78861582 is about 8880.4043826844. The cubic root of 78861582 is about 428.8332930114.

The spelling of 78861582 in words is "seventy-eight million, eight hundred sixty-one thousand, five hundred eighty-two".