2856820 has 12 divisors (see below), whose sum is σ = 5999364. Its totient is φ = 1142720.

The previous prime is 2856809. The next prime is 2856823. The reversal of 2856820 is 286582.

It can be written as a sum of positive squares in 2 ways, for example, as 509796 + 2347024 = 714^2 + 1532^2 .

It is a super-2 number, since 2×2856820² = 16322841024800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2856823) 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 3 ways as a sum of consecutive naturals, for example, 71401 + ... + 71440.

It is an arithmetic number, because the mean of its divisors is an integer number (499947).

2^2856820 is an apocalyptic number.

2856820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2856820 is an abundant number, since it is smaller than the sum of its proper divisors (3142544).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2856820 is a wasteful number, since it uses less digits than its factorization.

2856820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142850 (or 142848 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 2856820 is about 1690.2130043282. The cubic root of 2856820 is about 141.8929961582.

The spelling of 2856820 in words is "two million, eight hundred fifty-six thousand, eight hundred twenty".