2668581 has 6 divisors (see below), whose sum is σ = 3854630. Its totient is φ = 1779048.

The previous prime is 2668577. The next prime is 2668583. The reversal of 2668581 is 1858662.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 2452356 + 216225 = 1566^2 + 465^2 .

It is not a de Polignac number, because 2668581 - 2² = 2668577 is a prime.

It is a super-2 number, since 2×2668581² = 14242649107122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2668583) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 148246 + ... + 148263.

2^2668581 is an apocalyptic number.

It is an amenable number.

2668581 is a deficient number, since it is larger than the sum of its proper divisors (1186049).

2668581 is a wasteful number, since it uses less digits than its factorization.

2668581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296515 (or 296512 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 2668581 is about 1633.5791991820. The cubic root of 2668581 is about 138.7054300478.

It can be divided in two parts, 2668 and 581, that added together give a square (3249 = 57²).

The spelling of 2668581 in words is "two million, six hundred sixty-eight thousand, five hundred eighty-one".