2665621 has 4 divisors (see below), whose sum is σ = 3046432. Its totient is φ = 2284812.

The previous prime is 2665601. The next prime is 2665627. The reversal of 2665621 is 1265662.

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 2665621 - 2⁵ = 2665589 is a prime.

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 2665621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2665627) 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, 190395 + ... + 190408.

It is an arithmetic number, because the mean of its divisors is an integer number (761608).

2^2665621 is an apocalyptic number.

It is an amenable number.

2665621 is a deficient number, since it is larger than the sum of its proper divisors (380811).

2665621 is an equidigital number, since it uses as much as digits as its factorization.

2665621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 380810.

The product of its digits is 4320, while the sum is 28.

The square root of 2665621 is about 1632.6729617410. The cubic root of 2665621 is about 138.6541268811.

The spelling of 2665621 in words is "two million, six hundred sixty-five thousand, six hundred twenty-one".