2780881 has 4 divisors (see below), whose sum is σ = 2784564. Its totient is φ = 2777200.

The previous prime is 2780873. The next prime is 2780887. The reversal of 2780881 is 1880872.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 2073600 + 707281 = 1440^2 + 841^2 .

It is a cyclic number.

It is not a de Polignac number, because 2780881 - 2³ = 2780873 is a prime.

It is a super-2 number, since 2×2780881² = 15466598272322, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2780887) 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, 250 + ... + 2371.

It is an arithmetic number, because the mean of its divisors is an integer number (696141).

2^2780881 is an apocalyptic number.

It is an amenable number.

2780881 is a deficient number, since it is larger than the sum of its proper divisors (3683).

2780881 is a wasteful number, since it uses less digits than its factorization.

2780881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3682.

The product of its (nonzero) digits is 7168, while the sum is 34.

The square root of 2780881 is about 1667.5973734688. The cubic root of 2780881 is about 140.6244385821.

Subtracting from 2780881 its reverse (1880872), we obtain a palindrome (900009).

It can be divided in two parts, 27808 and 81, that added together give a square (27889 = 167²).

The spelling of 2780881 in words is "two million, seven hundred eighty thousand, eight hundred eighty-one".