1016821 has 16 divisors (see below), whose sum is σ = 1197504. Its totient is φ = 854784.

The previous prime is 1016789. The next prime is 1016839. The reversal of 1016821 is 1286101.

1016821 = T₃₈₉ + T₃₉₀ + ... + T₄₀₁.

It is a cyclic number.

It is not a de Polignac number, because 1016821 - 2⁵ = 1016789 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 (1016881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9450 + ... + 9556.

It is an arithmetic number, because the mean of its divisors is an integer number (74844).

2^1016821 is an apocalyptic number.

It is an amenable number.

1016821 is a deficient number, since it is larger than the sum of its proper divisors (180683).

1016821 is a wasteful number, since it uses less digits than its factorization.

1016821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180.

The product of its (nonzero) digits is 96, while the sum is 19.

The square root of 1016821 is about 1008.3754261187. The cubic root of 1016821 is about 100.5575852089.

The spelling of 1016821 in words is "one million, sixteen thousand, eight hundred twenty-one".