871821382 has 4 divisors (see below), whose sum is σ = 1307732076. Its totient is φ = 435910690.

The previous prime is 871821361. The next prime is 871821383. The reversal of 871821382 is 283128178.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 283128178 = 2 ⋅141564089.

It is a super-2 number, since 2×871821382² = 1520145044224779848, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (871821383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 217955344 + ... + 217955347.

It is an arithmetic number, because the mean of its divisors is an integer number (326933019).

Almost surely, 2^871821382 is an apocalyptic number.

871821382 is a deficient number, since it is larger than the sum of its proper divisors (435910694).

871821382 is a wasteful number, since it uses less digits than its factorization.

871821382 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 435910693.

The product of its digits is 43008, while the sum is 40.

The square root of 871821382 is about 29526.6215812104. The cubic root of 871821382 is about 955.3059999102.

The spelling of 871821382 in words is "eight hundred seventy-one million, eight hundred twenty-one thousand, three hundred eighty-two".