2506666 has 4 divisors (see below), whose sum is σ = 3760002. Its totient is φ = 1253332.

The previous prime is 2506661. The next prime is 2506681. The reversal of 2506666 is 6666052.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 2187441 + 319225 = 1479^2 + 565^2 .

2506666 is a modest number, since divided by 6666 gives 250 as remainder.

It is not an unprimeable number, because it can be changed into a prime (2506661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 626665 + ... + 626668.

2^2506666 is an apocalyptic number.

2506666 is a deficient number, since it is larger than the sum of its proper divisors (1253336).

2506666 is a wasteful number, since it uses less digits than its factorization.

2506666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1253335.

The product of its (nonzero) digits is 12960, while the sum is 31.

The square root of 2506666 is about 1583.2454010671. The cubic root of 2506666 is about 135.8414024924.

The spelling of 2506666 in words is "two million, five hundred six thousand, six hundred sixty-six".