2087821 has 8 divisors (see below), whose sum is σ = 2225664. Its totient is φ = 1951680.

The previous prime is 2087809. The next prime is 2087831. The reversal of 2087821 is 1287802.

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

It is a cyclic number.

It is not a de Polignac number, because 2087821 - 2¹³ = 2079629 is a prime.

It is an Ulam number.

It is a Duffinian number.

2087821 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 2087821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2087801) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2926 + ... + 3568.

It is an arithmetic number, because the mean of its divisors is an integer number (278208).

2^2087821 is an apocalyptic number.

It is an amenable number.

2087821 is a deficient number, since it is larger than the sum of its proper divisors (137843).

2087821 is a wasteful number, since it uses less digits than its factorization.

2087821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 851.

The product of its (nonzero) digits is 1792, while the sum is 28.

The square root of 2087821 is about 1444.9294100405. The cubic root of 2087821 is about 127.8098780655.

The spelling of 2087821 in words is "two million, eighty-seven thousand, eight hundred twenty-one".