638820331032 has 32 divisors (see below), whose sum is σ = 1719900892080. Its totient is φ = 196560101760.

The previous prime is 638820331031. The next prime is 638820331057. The reversal of 638820331032 is 230133028836.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638820331031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1023750219 + ... + 1023750842.

Almost surely, 2^638820331032 is an apocalyptic number.

It is an amenable number.

638820331032 is an abundant number, since it is smaller than the sum of its proper divisors (1081080561048).

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

638820331032 is a wasteful number, since it uses less digits than its factorization.

638820331032 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2047501083 (or 2047501079 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 39.

Adding to 638820331032 its reverse (230133028836), we get a palindrome (868953359868).

The spelling of 638820331032 in words is "six hundred thirty-eight billion, eight hundred twenty million, three hundred thirty-one thousand, thirty-two".