2508661 has 4 divisors (see below), whose sum is σ = 2515500. Its totient is φ = 2501824.

The previous prime is 2508641. The next prime is 2508677. The reversal of 2508661 is 1668052.

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 1664100 + 844561 = 1290^2 + 919^2 .

It is a cyclic number.

It is not a de Polignac number, because 2508661 - 2⁵ = 2508629 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2508641) 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, 2836 + ... + 3613.

It is an arithmetic number, because the mean of its divisors is an integer number (628875).

2^2508661 is an apocalyptic number.

It is an amenable number.

2508661 is a deficient number, since it is larger than the sum of its proper divisors (6839).

2508661 is an equidigital number, since it uses as much as digits as its factorization.

2508661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6838.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 2508661 is about 1583.8753107489. The cubic root of 2508661 is about 135.8774306581.

It can be divided in two parts, 250 and 8661, that added together give a triangular number (8911 = T₁₃₃).

The spelling of 2508661 in words is "two million, five hundred eight thousand, six hundred sixty-one".