2820261 has 4 divisors (see below), whose sum is σ = 3760352. Its totient is φ = 1880172.

The previous prime is 2820239. The next prime is 2820263. The reversal of 2820261 is 1620282.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2820261 - 2⁵ = 2820229 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2820263) 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, 470041 + ... + 470046.

It is an arithmetic number, because the mean of its divisors is an integer number (940088).

2^2820261 is an apocalyptic number.

It is an amenable number.

2820261 is a deficient number, since it is larger than the sum of its proper divisors (940091).

2820261 is an equidigital number, since it uses as much as digits as its factorization.

2820261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 940090.

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 2820261 is about 1679.3632721957. The cubic root of 2820261 is about 141.2851229648.

Adding to 2820261 its sum of digits (21), we get a palindrome (2820282).

It can be divided in two parts, 2820 and 261, that added together give a triangular number (3081 = T₇₈).

The spelling of 2820261 in words is "two million, eight hundred twenty thousand, two hundred sixty-one".