78239867 has 16 divisors (see below), whose sum is σ = 82672800. Its totient is φ = 73965312.

The previous prime is 78239809. The next prime is 78239893. The reversal of 78239867 is 76893287.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 78239867 - 2⁶ = 78239803 is a prime.

It is a super-2 number, since 2×78239867² = 12242953576355378, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78235867) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 224009 + ... + 224357.

It is an arithmetic number, because the mean of its divisors is an integer number (5167050).

Almost surely, 2^78239867 is an apocalyptic number.

78239867 is a deficient number, since it is larger than the sum of its proper divisors (4432933).

78239867 is a wasteful number, since it uses less digits than its factorization.

78239867 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 542.

The product of its digits is 1016064, while the sum is 50.

The square root of 78239867 is about 8845.3302369103. The cubic root of 78239867 is about 427.7033985310.

The spelling of 78239867 in words is "seventy-eight million, two hundred thirty-nine thousand, eight hundred sixty-seven".