821051 has 8 divisors (see below), whose sum is σ = 1023744. Its totient is φ = 639720.

The previous prime is 821039. The next prime is 821053. The reversal of 821051 is 150128.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-821051 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 (821053) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5255 + ... + 5408.

It is an arithmetic number, because the mean of its divisors is an integer number (127968).

2⁸²¹⁰⁵¹ is an apocalyptic number.

821051 is a deficient number, since it is larger than the sum of its proper divisors (202693).

821051 is a wasteful number, since it uses less digits than its factorization.

821051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10681.

The product of its (nonzero) digits is 80, while the sum is 17.

The square root of 821051 is about 906.1186456530. The cubic root of 821051 is about 93.6389880069.

Adding to 821051 its reverse (150128), we get a palindrome (971179).

The spelling of 821051 in words is "eight hundred twenty-one thousand, fifty-one".