2609921 has 4 divisors (see below), whose sum is σ = 2694144. Its totient is φ = 2525700.

The previous prime is 2609911. The next prime is 2609947. The reversal of 2609921 is 1299062.

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.

It is a cyclic number.

It is not a de Polignac number, because 2609921 - 2¹⁰ = 2608897 is a prime.

It is a super-3 number, since 3×2609921³ = 53333899743499610883, which contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (2609911) 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, 42065 + ... + 42126.

It is an arithmetic number, because the mean of its divisors is an integer number (673536).

2^2609921 is an apocalyptic number.

It is an amenable number.

2609921 is a deficient number, since it is larger than the sum of its proper divisors (84223).

2609921 is an equidigital number, since it uses as much as digits as its factorization.

2609921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84222.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 2609921 is about 1615.5249920691. The cubic root of 2609921 is about 137.6815629032.

The spelling of 2609921 in words is "two million, six hundred nine thousand, nine hundred twenty-one".