2666691 has 6 divisors (see below), whose sum is σ = 3851900. Its totient is φ = 1777788.

The previous prime is 2666683. The next prime is 2666693. The reversal of 2666691 is 1966662.

It is a happy number.

It is not a de Polignac number, because 2666691 - 2³ = 2666683 is a prime.

It is a super-2 number, since 2×2666691² = 14222481778962, which contains 22 as substring.

It is a Duffinian number.

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 5 ways as a sum of consecutive naturals, for example, 148141 + ... + 148158.

2^2666691 is an apocalyptic number.

2666691 is a deficient number, since it is larger than the sum of its proper divisors (1185209).

2666691 is a wasteful number, since it uses less digits than its factorization.

2666691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296305 (or 296302 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 2666691 is about 1633.0006123698. Note that the first 3 decimals coincide. The cubic root of 2666691 is about 138.6726766636.

The spelling of 2666691 in words is "two million, six hundred sixty-six thousand, six hundred ninety-one".