6640495 has 4 divisors (see below), whose sum is σ = 7968600. Its totient is φ = 5312392.

The previous prime is 6640493. The next prime is 6640499. The reversal of 6640495 is 5940466.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6640495 - 2¹ = 6640493 is a prime.

6640495 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 6640495.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6640493) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 664045 + ... + 664054.

It is an arithmetic number, because the mean of its divisors is an integer number (1992150).

Almost surely, 2^6640495 is an apocalyptic number.

6640495 is a deficient number, since it is larger than the sum of its proper divisors (1328105).

6640495 is a wasteful number, since it uses less digits than its factorization.

6640495 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1328104.

The product of its (nonzero) digits is 25920, while the sum is 34.

The square root of 6640495 is about 2576.9157921826. The cubic root of 6640495 is about 187.9605979746.

The spelling of 6640495 in words is "six million, six hundred forty thousand, four hundred ninety-five".