638550 has 96 divisors (see below), whose sum is σ = 1964160. Its totient is φ = 151200.

The previous prime is 638527. The next prime is 638567. The reversal of 638550 is 55836.

It is a super-2 number, since 2×638550² = 815492205000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nialpdrome in base 15.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 14829 + ... + 14871.

It is an arithmetic number, because the mean of its divisors is an integer number (20460).

2⁶³⁸⁵⁵⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (982080).

638550 is an abundant number, since it is smaller than the sum of its proper divisors (1325610).

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

638550 is a wasteful number, since it uses less digits than its factorization.

638550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 638550 is about 799.0932361120. The cubic root of 638550 is about 86.1122565077.

The spelling of 638550 in words is "six hundred thirty-eight thousand, five hundred fifty".