2817921 has 8 divisors (see below), whose sum is σ = 3771904. Its totient is φ = 1871280.

The previous prime is 2817917. The next prime is 2817929. The reversal of 2817921 is 1297182.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2817921 - 2² = 2817917 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2817929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 865 + ... + 2526.

It is an arithmetic number, because the mean of its divisors is an integer number (471488).

2^2817921 is an apocalyptic number.

It is an amenable number.

2817921 is a deficient number, since it is larger than the sum of its proper divisors (953983).

2817921 is a wasteful number, since it uses less digits than its factorization.

2817921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3671.

The product of its digits is 2016, while the sum is 30.

The square root of 2817921 is about 1678.6664350013. Note that the first 3 decimals coincide. The cubic root of 2817921 is about 141.2460369055.

The spelling of 2817921 in words is "two million, eight hundred seventeen thousand, nine hundred twenty-one".