2819881 has 4 divisors (see below), whose sum is σ = 2896132. Its totient is φ = 2743632.

The previous prime is 2819867. The next prime is 2819899. The reversal of 2819881 is 1889182.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1889182 = 2 ⋅944591.

It can be written as a sum of positive squares in 2 ways, for example, as 2205225 + 614656 = 1485^2 + 784^2 .

It is a cyclic number.

It is not a de Polignac number, because 2819881 - 2⁷ = 2819753 is a prime.

It is a super-2 number, since 2×2819881² = 15903457708322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37), and also a Moran number because the ratio is a prime number: 76213 = 2819881 / (2 + 8 + 1 + 9 + 8 + 8 + 1).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2819881.

It is not an unprimeable number, because it can be changed into a prime (2819801) 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, 38070 + ... + 38143.

It is an arithmetic number, because the mean of its divisors is an integer number (724033).

2^2819881 is an apocalyptic number.

It is an amenable number.

2819881 is a deficient number, since it is larger than the sum of its proper divisors (76251).

2819881 is an equidigital number, since it uses as much as digits as its factorization.

2819881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76250.

The product of its digits is 9216, while the sum is 37.

The square root of 2819881 is about 1679.2501302665. The cubic root of 2819881 is about 141.2787771268.

The spelling of 2819881 in words is "two million, eight hundred nineteen thousand, eight hundred eighty-one".