2140821 has 12 divisors (see below), whose sum is σ = 3132480. Its totient is φ = 1408680.

The previous prime is 2140811. The next prime is 2140823. The reversal of 2140821 is 1280412.

It is not a de Polignac number, because 2140821 - 2⁹ = 2140309 is a prime.

It is a super-2 number, since 2×2140821² = 9166229108082, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2140794 and 2140803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2140823) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 795 + ... + 2216.

It is an arithmetic number, because the mean of its divisors is an integer number (261040).

2^2140821 is an apocalyptic number.

It is an amenable number.

2140821 is a deficient number, since it is larger than the sum of its proper divisors (991659).

2140821 is a wasteful number, since it uses less digits than its factorization.

2140821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3096 (or 3093 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 2140821 is about 1463.1544689471. The cubic root of 2140821 is about 128.8823517240.

The spelling of 2140821 in words is "two million, one hundred forty thousand, eight hundred twenty-one".