78578231 has 4 divisors (see below), whose sum is σ = 78612864. Its totient is φ = 78543600.

The previous prime is 78578221. The next prime is 78578237. The reversal of 78578231 is 13287587.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 78578231 - 2¹⁰ = 78577207 is a prime.

It is a super-2 number, since 2×78578231² = 12349076774178722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78578237) 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 3 ways as a sum of consecutive naturals, for example, 13655 + ... + 18536.

It is an arithmetic number, because the mean of its divisors is an integer number (19653216).

Almost surely, 2^78578231 is an apocalyptic number.

78578231 is a deficient number, since it is larger than the sum of its proper divisors (34633).

78578231 is a wasteful number, since it uses less digits than its factorization.

78578231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34632.

The product of its digits is 94080, while the sum is 41.

The square root of 78578231 is about 8864.4363046953. The cubic root of 78578231 is about 428.3190748920.

The spelling of 78578231 in words is "seventy-eight million, five hundred seventy-eight thousand, two hundred thirty-one".