647237838 has 64 divisors (see below), whose sum is σ = 1485933120. Its totient is φ = 186181632.

The previous prime is 647237797. The next prime is 647237839. The reversal of 647237838 is 838732746.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647237839) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 206628 + ... + 209736.

It is an arithmetic number, because the mean of its divisors is an integer number (23217705).

Almost surely, 2^647237838 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 647237838, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (742966560).

647237838 is an abundant number, since it is smaller than the sum of its proper divisors (838695282).

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

647237838 is a wasteful number, since it uses less digits than its factorization.

647237838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3301.

The product of its digits is 1354752, while the sum is 48.

The square root of 647237838 is about 25440.8694426900. The cubic root of 647237838 is about 865.0103412398.

The spelling of 647237838 in words is "six hundred forty-seven million, two hundred thirty-seven thousand, eight hundred thirty-eight".