2909881 has 4 divisors (see below), whose sum is σ = 3133732. Its totient is φ = 2686032.

The previous prime is 2909867. The next prime is 2909909. The reversal of 2909881 is 1889092.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 614656 + 2295225 = 784^2 + 1515^2 .

It is a cyclic number.

It is not a de Polignac number, because 2909881 - 2⁵ = 2909849 is a prime.

It is a super-2 number, since 2×2909881² = 16934814868322, which contains 22 as substring.

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 2909881.

It is not an unprimeable number, because it can be changed into a prime (2909281) 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, 111906 + ... + 111931.

It is an arithmetic number, because the mean of its divisors is an integer number (783433).

2^2909881 is an apocalyptic number.

It is an amenable number.

2909881 is a deficient number, since it is larger than the sum of its proper divisors (223851).

2909881 is a wasteful number, since it uses less digits than its factorization.

2909881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223850.

The product of its (nonzero) digits is 10368, while the sum is 37.

The square root of 2909881 is about 1705.8373310489. The cubic root of 2909881 is about 142.7660935539.

The spelling of 2909881 in words is "two million, nine hundred nine thousand, eight hundred eighty-one".