82817257 has 4 divisors (see below), whose sum is σ = 87176080. Its totient is φ = 78458436.

The previous prime is 82817249. The next prime is 82817261. The reversal of 82817257 is 75271828.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 82817257 - 2³ = 82817249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (82817237) 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, 2179383 + ... + 2179420.

It is an arithmetic number, because the mean of its divisors is an integer number (21794020).

Almost surely, 2^82817257 is an apocalyptic number.

It is an amenable number.

82817257 is a deficient number, since it is larger than the sum of its proper divisors (4358823).

82817257 is a wasteful number, since it uses less digits than its factorization.

82817257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4358822.

The product of its digits is 62720, while the sum is 40.

The square root of 82817257 is about 9100.3987275284. The cubic root of 82817257 is about 435.8866962126.

The spelling of 82817257 in words is "eighty-two million, eight hundred seventeen thousand, two hundred fifty-seven".