638028243 has 24 divisors (see below), whose sum is σ = 942809088. Its totient is φ = 415593072.

The previous prime is 638028239. The next prime is 638028271. The reversal of 638028243 is 342820836.

It is not a de Polignac number, because 638028243 - 2² = 638028239 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 638028198 and 638028207.

It is not an unprimeable number, because it can be changed into a prime (638028233) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 382830 + ... + 384492.

It is an arithmetic number, because the mean of its divisors is an integer number (39283712).

Almost surely, 2^638028243 is an apocalyptic number.

638028243 is a deficient number, since it is larger than the sum of its proper divisors (304780845).

638028243 is a wasteful number, since it uses less digits than its factorization.

638028243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2623 (or 2620 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The square root of 638028243 is about 25259.2209499818. The cubic root of 638028243 is about 860.8879610757.

The spelling of 638028243 in words is "six hundred thirty-eight million, twenty-eight thousand, two hundred forty-three".