78428307 has 6 divisors (see below), whose sum is σ = 104591532. Its totient is φ = 52275312.

The previous prime is 78428303. The next prime is 78428309. The reversal of 78428307 is 70382487.

It is not a de Polignac number, because 78428307 - 2² = 78428303 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78428303) 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 5 ways as a sum of consecutive naturals, for example, 12783 + ... + 17895.

It is an arithmetic number, because the mean of its divisors is an integer number (17431922).

Almost surely, 2^78428307 is an apocalyptic number.

78428307 is a deficient number, since it is larger than the sum of its proper divisors (26163225).

78428307 is an frugal number, since it uses more digits than its factorization.

78428307 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10229 (or 5116 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 39.

The square root of 78428307 is about 8855.9757790997. The cubic root of 78428307 is about 428.0464964626.

The spelling of 78428307 in words is "seventy-eight million, four hundred twenty-eight thousand, three hundred seven".