82281391 has 4 divisors (see below), whose sum is σ = 82594512. Its totient is φ = 81968272.

The previous prime is 82281379. The next prime is 82281421. The reversal of 82281391 is 19318228.

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 82281391 - 2⁷ = 82281263 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82251391) 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, 156166 + ... + 156691.

It is an arithmetic number, because the mean of its divisors is an integer number (20648628).

Almost surely, 2^82281391 is an apocalyptic number.

82281391 is a deficient number, since it is larger than the sum of its proper divisors (313121).

82281391 is a wasteful number, since it uses less digits than its factorization.

82281391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313120.

The product of its digits is 6912, while the sum is 34.

The square root of 82281391 is about 9070.9090503653. The cubic root of 82281391 is about 434.9445316158.

The spelling of 82281391 in words is "eighty-two million, two hundred eighty-one thousand, three hundred ninety-one".