2666521 has 16 divisors (see below), whose sum is σ = 3245760. Its totient is φ = 2157120.

The previous prime is 2666519. The next prime is 2666537. The reversal of 2666521 is 1256662.

It is a cyclic number.

It is not a de Polignac number, because 2666521 - 2¹ = 2666519 is a prime.

It is a super-2 number, since 2×2666521² = 14220668486882, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

2666521 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 2666521.

It is not an unprimeable number, because it can be changed into a prime (2666561) 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, 3826 + ... + 4468.

It is an arithmetic number, because the mean of its divisors is an integer number (202860).

2^2666521 is an apocalyptic number.

It is an amenable number.

2666521 is a deficient number, since it is larger than the sum of its proper divisors (579239).

2666521 is a wasteful number, since it uses less digits than its factorization.

2666521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 696.

The product of its digits is 4320, while the sum is 28.

The square root of 2666521 is about 1632.9485601206. The cubic root of 2666521 is about 138.6697298335.

The spelling of 2666521 in words is "two million, six hundred sixty-six thousand, five hundred twenty-one".