6640938 has 24 divisors (see below), whose sum is σ = 14499108. Its totient is φ = 2196672.

The previous prime is 6640927. The next prime is 6640939. The reversal of 6640938 is 8390466.

6640938 is a `hidden beast` number, since 6 + 640 + 9 + 3 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 6640929 + 9 = 2577^2 + 3^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (6640939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1120 + ... + 3812.

Almost surely, 2^6640938 is an apocalyptic number.

6640938 is an abundant number, since it is smaller than the sum of its proper divisors (7858170).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6640938 is a wasteful number, since it uses less digits than its factorization.

6640938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2838 (or 2835 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 6640938 is about 2577.0017462159. The cubic root of 6640938 is about 187.9647776175.

The spelling of 6640938 in words is "six million, six hundred forty thousand, nine hundred thirty-eight".