6669645 has 16 divisors (see below), whose sum is σ = 10819392. Its totient is φ = 3507840.

The previous prime is 6669643. The next prime is 6669647. The reversal of 6669645 is 5469666.

6669645 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (6669643) and next prime (6669647).

It is not a de Polignac number, because 6669645 - 2¹ = 6669643 is a prime.

It is a super-3 number, since 3×6669645³ (a number of 21 digits) contains 333 as substring.

6669645 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 6669597 and 6669606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6669643) 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, 1951 + ... + 4140.

It is an arithmetic number, because the mean of its divisors is an integer number (676212).

Almost surely, 2^6669645 is an apocalyptic number.

It is an amenable number.

6669645 is a deficient number, since it is larger than the sum of its proper divisors (4149747).

6669645 is a wasteful number, since it uses less digits than its factorization.

6669645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6172.

The product of its digits is 233280, while the sum is 42.

The square root of 6669645 is about 2582.5655848400. The cubic root of 6669645 is about 188.2352287933.

The spelling of 6669645 in words is "six million, six hundred sixty-nine thousand, six hundred forty-five".