2557666 has 8 divisors (see below), whose sum is σ = 4038480. Its totient is φ = 1211508.

The previous prime is 2557663. The next prime is 2557673. The reversal of 2557666 is 6667552.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (2557663) 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, 33616 + ... + 33691.

It is an arithmetic number, because the mean of its divisors is an integer number (504810).

2^2557666 is an apocalyptic number.

2557666 is a deficient number, since it is larger than the sum of its proper divisors (1480814).

2557666 is a wasteful number, since it uses less digits than its factorization.

2557666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67328.

The product of its digits is 75600, while the sum is 37.

The square root of 2557666 is about 1599.2704586780. The cubic root of 2557666 is about 136.7564893030.

It can be divided in two parts, 2557 and 666, that added together give a palindrome (3223).

The spelling of 2557666 in words is "two million, five hundred fifty-seven thousand, six hundred sixty-six".