78866442 has 12 divisors (see below), whose sum is σ = 170877330. Its totient is φ = 26288808.

The previous prime is 78866441. The next prime is 78866453. The reversal of 78866442 is 24466887.

It can be written as a sum of positive squares in only one way, i.e., 74494161 + 4372281 = 8631^2 + 2091^2 .

It is not an unprimeable number, because it can be changed into a prime (78866441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2190717 + ... + 2190752.

Almost surely, 2^78866442 is an apocalyptic number.

78866442 is an abundant number, since it is smaller than the sum of its proper divisors (92010888).

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

78866442 is a wasteful number, since it uses less digits than its factorization.

78866442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4381477 (or 4381474 counting only the distinct ones).

The product of its digits is 516096, while the sum is 45.

The square root of 78866442 is about 8880.6780146563. The cubic root of 78866442 is about 428.8421020620.

The spelling of 78866442 in words is "seventy-eight million, eight hundred sixty-six thousand, four hundred forty-two".