2820421 has 8 divisors (see below), whose sum is σ = 2966400. Its totient is φ = 2676432.

The previous prime is 2820407. The next prime is 2820479. The reversal of 2820421 is 1240282.

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 2820421 - 2²¹ = 723269 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 (2820401) 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, 3016 + ... + 3838.

It is an arithmetic number, because the mean of its divisors is an integer number (370800).

2^2820421 is an apocalyptic number.

It is an amenable number.

2820421 is a deficient number, since it is larger than the sum of its proper divisors (145979).

2820421 is a wasteful number, since it uses less digits than its factorization.

2820421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 995.

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 2820421 is about 1679.4109086224. The cubic root of 2820421 is about 141.2877947261.

It can be divided in two parts, 28 and 20421, that added together give a square (20449 = 143²).

The spelling of 2820421 in words is "two million, eight hundred twenty thousand, four hundred twenty-one".