78065571 has 4 divisors (see below), whose sum is σ = 104087432. Its totient is φ = 52043712.

The previous prime is 78065557. The next prime is 78065587. The reversal of 78065571 is 17556087.

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

It is not a de Polignac number, because 78065571 - 2⁵ = 78065539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78065521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13010926 + ... + 13010931.

It is an arithmetic number, because the mean of its divisors is an integer number (26021858).

Almost surely, 2^78065571 is an apocalyptic number.

78065571 is a deficient number, since it is larger than the sum of its proper divisors (26021861).

78065571 is a wasteful number, since it uses less digits than its factorization.

78065571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26021860.

The product of its (nonzero) digits is 58800, while the sum is 39.

The square root of 78065571 is about 8835.4723133514. The cubic root of 78065571 is about 427.3855622008.

The spelling of 78065571 in words is "seventy-eight million, sixty-five thousand, five hundred seventy-one".