78291 has 6 divisors (see below), whose sum is σ = 113100. Its totient is φ = 52188.

The previous prime is 78283. The next prime is 78301. The reversal of 78291 is 19287.

It is not a de Polignac number, because 78291 - 2³ = 78283 is a prime.

It is a super-2 number, since 2×78291² = 12258961362, which contains 22 as substring.

78291 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (78241) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4341 + ... + 4358.

It is an arithmetic number, because the mean of its divisors is an integer number (18850).

2⁷⁸²⁹¹ is an apocalyptic number.

78291 is a deficient number, since it is larger than the sum of its proper divisors (34809).

78291 is a wasteful number, since it uses less digits than its factorization.

78291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8705 (or 8702 counting only the distinct ones).

The product of its digits is 1008, while the sum is 27.

The square root of 78291 is about 279.8052894425. The cubic root of 78291 is about 42.7796552214.

The spelling of 78291 in words is "seventy-eight thousand, two hundred ninety-one".