638547630 has 96 divisors (see below), whose sum is σ = 1848697344. Its totient is φ = 138255552.

The previous prime is 638547617. The next prime is 638547647. The reversal of 638547630 is 36745836.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 71599 + ... + 80021.

It is an arithmetic number, because the mean of its divisors is an integer number (19257264).

Almost surely, 2^638547630 is an apocalyptic number.

It is a pronic number, being equal to 25269×25270.

It is a practical number, because each smaller number is the sum of distinct divisors of 638547630, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (924348672).

638547630 is an abundant number, since it is smaller than the sum of its proper divisors (1210149714).

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

638547630 is a wasteful number, since it uses less digits than its factorization.

638547630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8478 (or 8459 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 42.

The square root of 638547630 is about 25269.4999950533. The cubic root of 638547630 is about 861.1214997136.

The spelling of 638547630 in words is "six hundred thirty-eight million, five hundred forty-seven thousand, six hundred thirty".