6638438 has 4 divisors (see below), whose sum is σ = 9957660. Its totient is φ = 3319218.

The previous prime is 6638407. The next prime is 6638459. The reversal of 6638438 is 8348366.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1659608 + ... + 1659611.

It is an arithmetic number, because the mean of its divisors is an integer number (2489415).

Almost surely, 2^6638438 is an apocalyptic number.

6638438 is a deficient number, since it is larger than the sum of its proper divisors (3319222).

6638438 is a wasteful number, since it uses less digits than its factorization.

6638438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3319221.

The product of its digits is 82944, while the sum is 38.

The square root of 6638438 is about 2576.5166407380. The cubic root of 6638438 is about 187.9411880320.

The spelling of 6638438 in words is "six million, six hundred thirty-eight thousand, four hundred thirty-eight".