6638730 has 64 divisors (see below), whose sum is σ = 18448128. Its totient is φ = 1497600.

The previous prime is 6638701. The next prime is 6638741. The reversal of 6638730 is 378366.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 6638691 and 6638700.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21054 + ... + 21366.

It is an arithmetic number, because the mean of its divisors is an integer number (288252).

Almost surely, 2^6638730 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6638730, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9224064).

6638730 is an abundant number, since it is smaller than the sum of its proper divisors (11809398).

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

6638730 is a wasteful number, since it uses less digits than its factorization.

6638730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 431.

The product of its (nonzero) digits is 18144, while the sum is 33.

The square root of 6638730 is about 2576.5733057687. The cubic root of 6638730 is about 187.9439436011.

The spelling of 6638730 in words is "six million, six hundred thirty-eight thousand, seven hundred thirty".