827811021 has 16 divisors (see below), whose sum is σ = 1123739136. Its totient is φ = 541944576.

The previous prime is 827810989. The next prime is 827811043. The reversal of 827811021 is 120118728.

It is a happy number.

It is not a de Polignac number, because 827811021 - 2⁵ = 827810989 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 827811021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (827811091) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42916 + ... + 59138.

It is an arithmetic number, because the mean of its divisors is an integer number (70233696).

Almost surely, 2^827811021 is an apocalyptic number.

It is an amenable number.

827811021 is a deficient number, since it is larger than the sum of its proper divisors (295928115).

827811021 is a wasteful number, since it uses less digits than its factorization.

827811021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16532.

The product of its (nonzero) digits is 1792, while the sum is 30.

The square root of 827811021 is about 28771.7052153674. The cubic root of 827811021 is about 938.9527423107.

Adding to 827811021 its reverse (120118728), we get a palindrome (947929749).

The spelling of 827811021 in words is "eight hundred twenty-seven million, eight hundred eleven thousand, twenty-one".