821004471 has 32 divisors (see below), whose sum is σ = 1438003200. Its totient is φ = 452964960.

The previous prime is 821004467. The next prime is 821004487. The reversal of 821004471 is 174400128.

821004471 is a `hidden beast` number, since 8 + 210 + 0 + 447 + 1 = 666.

It is not a de Polignac number, because 821004471 - 2² = 821004467 is a prime.

It is a super-3 number, since 3×821004471³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821004071) 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 in 31 ways as a sum of consecutive naturals, for example, 69415 + ... + 80376.

It is an arithmetic number, because the mean of its divisors is an integer number (44937600).

Almost surely, 2^821004471 is an apocalyptic number.

821004471 is a deficient number, since it is larger than the sum of its proper divisors (616998729).

821004471 is a wasteful number, since it uses less digits than its factorization.

821004471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149836 (or 149830 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 821004471 is about 28653.1755831705. The cubic root of 821004471 is about 936.3721913148.

Adding to 821004471 its reverse (174400128), we get a palindrome (995404599).

The spelling of 821004471 in words is "eight hundred twenty-one million, four thousand, four hundred seventy-one".