638555630 has 48 divisors (see below), whose sum is σ = 1188554256. Its totient is φ = 246986880.

The previous prime is 638555609. The next prime is 638555651. The reversal of 638555630 is 36555836.

It is an interprime number because it is at equal distance from previous prime (638555609) and next prime (638555651).

It is a Curzon number.

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 23 ways as a sum of consecutive naturals, for example, 3026225 + ... + 3026435.

It is an arithmetic number, because the mean of its divisors is an integer number (24761547).

Almost surely, 2^638555630 is an apocalyptic number.

638555630 is a deficient number, since it is larger than the sum of its proper divisors (549998626).

638555630 is a wasteful number, since it uses less digits than its factorization.

638555630 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 449 (or 402 counting only the distinct ones).

The product of its (nonzero) digits is 324000, while the sum is 41.

The square root of 638555630 is about 25269.6582881526. The cubic root of 638555630 is about 861.1250958657.

The spelling of 638555630 in words is "six hundred thirty-eight million, five hundred fifty-five thousand, six hundred thirty".