823172217 has 32 divisors (see below), whose sum is σ = 1290240000. Its totient is φ = 466606224.

The previous prime is 823172201. The next prime is 823172219. The reversal of 823172217 is 712271328.

It is not a de Polignac number, because 823172217 - 2⁴ = 823172201 is a prime.

It is a super-2 number, since 2×823172217² = 1355224997681390178, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (823172219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 127534 + ... + 133832.

It is an arithmetic number, because the mean of its divisors is an integer number (40320000).

Almost surely, 2^823172217 is an apocalyptic number.

It is an amenable number.

823172217 is a deficient number, since it is larger than the sum of its proper divisors (467067783).

823172217 is a wasteful number, since it uses less digits than its factorization.

823172217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6450 (or 6436 counting only the distinct ones).

The product of its digits is 9408, while the sum is 33.

The square root of 823172217 is about 28690.9779721779. The cubic root of 823172217 is about 937.1955864275.

The spelling of 823172217 in words is "eight hundred twenty-three million, one hundred seventy-two thousand, two hundred seventeen".