2685581 has 2 divisors, whose sum is σ = 2685582. Its totient is φ = 2685580.

The previous prime is 2685577. The next prime is 2685583. The reversal of 2685581 is 1855862.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2669956 + 15625 = 1634^2 + 125^2 .

It is a cyclic number.

It is not a de Polignac number, because 2685581 - 2² = 2685577 is a prime.

It is a super-2 number, since 2×2685581² = 14424690615122, which contains 22 as substring.

Together with 2685583, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2685583) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1342790 + 1342791.

It is an arithmetic number, because the mean of its divisors is an integer number (1342791).

2^2685581 is an apocalyptic number.

It is an amenable number.

2685581 is a deficient number, since it is larger than the sum of its proper divisors (1).

2685581 is an equidigital number, since it uses as much as digits as its factorization.

2685581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 19200, while the sum is 35.

The square root of 2685581 is about 1638.7742370443. The cubic root of 2685581 is about 138.9993444063. Note that the first 3 decimals are identical.

The spelling of 2685581 in words is "two million, six hundred eighty-five thousand, five hundred eighty-one".