1086821 has 4 divisors (see below), whose sum is σ = 1094892. Its totient is φ = 1078752.

The previous prime is 1086817. The next prime is 1086859. The reversal of 1086821 is 1286801.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1286801 = 283 ⋅4547.

It can be written as a sum of positive squares in 2 ways, for example, as 470596 + 616225 = 686^2 + 785^2 .

It is a cyclic number.

It is not a de Polignac number, because 1086821 - 2² = 1086817 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1086881) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3830 + ... + 4103.

It is an arithmetic number, because the mean of its divisors is an integer number (273723).

2^1086821 is an apocalyptic number.

It is an amenable number.

1086821 is a deficient number, since it is larger than the sum of its proper divisors (8071).

1086821 is an equidigital number, since it uses as much as digits as its factorization.

1086821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8070.

The product of its (nonzero) digits is 768, while the sum is 26.

The square root of 1086821 is about 1042.5070743165. The cubic root of 1086821 is about 102.8140989610.

The spelling of 1086821 in words is "one million, eighty-six thousand, eight hundred twenty-one".