6487666 has 4 divisors (see below), whose sum is σ = 9731502. Its totient is φ = 3243832.

The previous prime is 6487643. The next prime is 6487667. The reversal of 6487666 is 6667846.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6667846 = 2 ⋅3333923.

It can be written as a sum of positive squares in only one way, i.e., 6145441 + 342225 = 2479^2 + 585^2 .

It is a super-3 number, since 3×6487666³ (a number of 21 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (6487667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1621915 + ... + 1621918.

Almost surely, 2^6487666 is an apocalyptic number.

6487666 is a deficient number, since it is larger than the sum of its proper divisors (3243836).

6487666 is a wasteful number, since it uses less digits than its factorization.

6487666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3243835.

The product of its digits is 290304, while the sum is 43.

The square root of 6487666 is about 2547.0897118084. The cubic root of 6487666 is about 186.5074400403.

The spelling of 6487666 in words is "six million, four hundred eighty-seven thousand, six hundred sixty-six".