6638140 has 12 divisors (see below), whose sum is σ = 13940136. Its totient is φ = 2655248.

The previous prime is 6638131. The next prime is 6638141. The reversal of 6638140 is 418366.

It is a junction number, because it is equal to n+sod(n) for n = 6638099 and 6638108.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6638141) 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 3 ways as a sum of consecutive naturals, for example, 165934 + ... + 165973.

It is an arithmetic number, because the mean of its divisors is an integer number (1161678).

Almost surely, 2^6638140 is an apocalyptic number.

It is an amenable number.

6638140 is an abundant number, since it is smaller than the sum of its proper divisors (7301996).

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

6638140 is a wasteful number, since it uses less digits than its factorization.

6638140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331916 (or 331914 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 6638140 is about 2576.4588100725. The cubic root of 6638140 is about 187.9383757584.

The spelling of 6638140 in words is "six million, six hundred thirty-eight thousand, one hundred forty".