72817 has 2 divisors, whose sum is σ = 72818. Its totient is φ = 72816.

The previous prime is 72797. The next prime is 72823. The reversal of 72817 is 71827.

It is a happy number.

72817 is nontrivially palindromic in base 2.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62001 + 10816 = 249^2 + 104^2 .

It is a cyclic number.

It is not a de Polignac number, because 72817 - 2⁷ = 72689 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 72791 and 72800.

It is not a weakly prime, because it can be changed into another prime (72617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36408 + 36409.

It is an arithmetic number, because the mean of its divisors is an integer number (36409).

2⁷²⁸¹⁷ is an apocalyptic number.

It is an amenable number.

72817 is a deficient number, since it is larger than the sum of its proper divisors (1).

72817 is an equidigital number, since it uses as much as digits as its factorization.

72817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 784, while the sum is 25.

The square root of 72817 is about 269.8462525217. The cubic root of 72817 is about 41.7584394953.

Subtracting from 72817 its reverse (71827), we obtain a triangular number (990 = T₄₄).

The spelling of 72817 in words is "seventy-two thousand, eight hundred seventeen".