2666690 has 32 divisors (see below), whose sum is σ = 5258736. Its totient is φ = 967680.

The previous prime is 2666683. The next prime is 2666693. The reversal of 2666690 is 966662.

It is a Cunningham number, because it is equal to 1633²+1.

It can be written as a sum of positive squares in 8 ways, for example, as 958441 + 1708249 = 979^2 + 1307^2 .

It is a super-2 number, since 2×2666690² = 14222471112200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2666690.

It is not an unprimeable number, because it can be changed into a prime (2666693) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9350 + ... + 9630.

2^2666690 is an apocalyptic number.

2666690 is a deficient number, since it is larger than the sum of its proper divisors (2592046).

2666690 is a wasteful number, since it uses less digits than its factorization.

2666690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 374.

The product of its (nonzero) digits is 23328, while the sum is 35.

The square root of 2666690 is about 1633.0003061849. Note that the first 3 decimals coincide. The cubic root of 2666690 is about 138.6726593297.

The spelling of 2666690 in words is "two million, six hundred sixty-six thousand, six hundred ninety".