821086331 has 6 divisors (see below), whose sum is σ = 889105500. Its totient is φ = 757925688.

The previous prime is 821086307. The next prime is 821086337. The reversal of 821086331 is 133680128.

It is a happy number.

821086331 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-821086331 is a prime.

It is a super-2 number, since 2×821086331² = 1348365525910083122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (821086337) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2429081 + ... + 2429418.

It is an arithmetic number, because the mean of its divisors is an integer number (148184250).

Almost surely, 2^821086331 is an apocalyptic number.

821086331 is a deficient number, since it is larger than the sum of its proper divisors (68019169).

821086331 is a wasteful number, since it uses less digits than its factorization.

821086331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4858525 (or 4858512 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 821086331 is about 28654.6040105251. The cubic root of 821086331 is about 936.4033112753.

The spelling of 821086331 in words is "eight hundred twenty-one million, eighty-six thousand, three hundred thirty-one".