6638747 has 4 divisors (see below), whose sum is σ = 6644016. Its totient is φ = 6633480.

The previous prime is 6638741. The next prime is 6638773. The reversal of 6638747 is 7478366.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 6638747 - 2⁸ = 6638491 is a prime.

It is a d-powerful number, because it can be written as 6⁴ + 6⁶ + 3⁷ + 8 + 7⁷ + 4⁴ + 7⁸ .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6638741) 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, 497 + ... + 3677.

It is an arithmetic number, because the mean of its divisors is an integer number (1661004).

Almost surely, 2^6638747 is an apocalyptic number.

6638747 is a deficient number, since it is larger than the sum of its proper divisors (5269).

6638747 is a wasteful number, since it uses less digits than its factorization.

6638747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5268.

The product of its digits is 169344, while the sum is 41.

The square root of 6638747 is about 2576.5766047219. The cubic root of 6638747 is about 187.9441040255.

The spelling of 6638747 in words is "six million, six hundred thirty-eight thousand, seven hundred forty-seven".