817997871 has 8 divisors (see below), whose sum is σ = 1091795584. Its totient is φ = 544766040.

The previous prime is 817997849. The next prime is 817997879. The reversal of 817997871 is 178799718.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 817997871 - 2⁷ = 817997743 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 (817997879) 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 7 ways as a sum of consecutive naturals, for example, 138085 + ... + 143886.

It is an arithmetic number, because the mean of its divisors is an integer number (136474448).

Almost surely, 2^817997871 is an apocalyptic number.

817997871 is a deficient number, since it is larger than the sum of its proper divisors (273797713).

817997871 is a wasteful number, since it uses less digits than its factorization.

817997871 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 282941.

The product of its digits is 1778112, while the sum is 57.

The square root of 817997871 is about 28600.6620727563. The cubic root of 817997871 is about 935.2277638194.

The spelling of 817997871 in words is "eight hundred seventeen million, nine hundred ninety-seven thousand, eight hundred seventy-one".