638393229 has 6 divisors (see below), whose sum is σ = 922123566. Its totient is φ = 425595480.

The previous prime is 638393213. The next prime is 638393251. The reversal of 638393229 is 922393836.

638393229 is a `hidden beast` number, since 6 + 38 + 393 + 229 = 666.

It can be written as a sum of positive squares in only one way, i.e., 344956329 + 293436900 = 18573^2 + 17130^2 .

It is not a de Polignac number, because 638393229 - 2⁴ = 638393213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638393029) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 35466282 + ... + 35466299.

It is an arithmetic number, because the mean of its divisors is an integer number (153687261).

Almost surely, 2^638393229 is an apocalyptic number.

It is an amenable number.

638393229 is a deficient number, since it is larger than the sum of its proper divisors (283730337).

638393229 is a wasteful number, since it uses less digits than its factorization.

638393229 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70932587 (or 70932584 counting only the distinct ones).

The product of its digits is 419904, while the sum is 45.

The square root of 638393229 is about 25266.4447241791. Note that the first 3 decimals coincide. The cubic root of 638393229 is about 861.0520876435.

The spelling of 638393229 in words is "six hundred thirty-eight million, three hundred ninety-three thousand, two hundred twenty-nine".