2891820 has 24 divisors (see below), whose sum is σ = 8097264. Its totient is φ = 771136.

The previous prime is 2891789. The next prime is 2891821. The reversal of 2891820 is 281982.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (2891821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24039 + ... + 24158.

It is an arithmetic number, because the mean of its divisors is an integer number (337386).

2^2891820 is an apocalyptic number.

2891820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2891820 is an abundant number, since it is smaller than the sum of its proper divisors (5205444).

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

2891820 is a wasteful number, since it uses less digits than its factorization.

2891820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48209 (or 48207 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 30.

The square root of 2891820 is about 1700.5352098678. The cubic root of 2891820 is about 142.4701076111.

The spelling of 2891820 in words is "two million, eight hundred ninety-one thousand, eight hundred twenty".