78821307 has 12 divisors (see below), whose sum is σ = 114451584. Its totient is φ = 52271280.

The previous prime is 78821293. The next prime is 78821317. The reversal of 78821307 is 70312887.

It is not a de Polignac number, because 78821307 - 2⁶ = 78821243 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78821317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21208 + ... + 24645.

It is an arithmetic number, because the mean of its divisors is an integer number (9537632).

Almost surely, 2^78821307 is an apocalyptic number.

78821307 is a deficient number, since it is larger than the sum of its proper divisors (35630277).

78821307 is a wasteful number, since it uses less digits than its factorization.

78821307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46050 (or 46047 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 36.

The square root of 78821307 is about 8878.1364598659. The cubic root of 78821307 is about 428.7602781523.

The spelling of 78821307 in words is "seventy-eight million, eight hundred twenty-one thousand, three hundred seven".