2881921 has 4 divisors (see below), whose sum is σ = 3293632. Its totient is φ = 2470212.

The previous prime is 2881897. The next prime is 2881937. The reversal of 2881921 is 1291882.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1291882 = 2 ⋅645941.

It is a cyclic number.

It is not a de Polignac number, because 2881921 - 2⁵ = 2881889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2881951) 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, 205845 + ... + 205858.

It is an arithmetic number, because the mean of its divisors is an integer number (823408).

2^2881921 is an apocalyptic number.

It is an amenable number.

2881921 is a deficient number, since it is larger than the sum of its proper divisors (411711).

2881921 is an equidigital number, since it uses as much as digits as its factorization.

2881921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411710.

The product of its digits is 2304, while the sum is 31.

The square root of 2881921 is about 1697.6221605528. The cubic root of 2881921 is about 142.3073584454.

It can be divided in two parts, 288 and 1921, that added together give a square (2209 = 47²).

The spelling of 2881921 in words is "two million, eight hundred eighty-one thousand, nine hundred twenty-one".