638610102 has 192 divisors, whose sum is σ = 1686528000. Its totient is φ = 178319232.

The previous prime is 638610101. The next prime is 638610107. The reversal of 638610102 is 201016836.

638610102 is a `hidden beast` number, since 6 + 38 + 610 + 10 + 2 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638610101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 5028363 + ... + 5028489.

It is an arithmetic number, because the mean of its divisors is an integer number (8784000).

Almost surely, 2^638610102 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638610102, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (843264000).

638610102 is an abundant number, since it is smaller than the sum of its proper divisors (1047917898).

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

638610102 is a wasteful number, since it uses less digits than its factorization.

638610102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212 (or 193 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 638610102 is about 25270.7360795051. The cubic root of 638610102 is about 861.1495812669.

Adding to 638610102 its reverse (201016836), we get a palindrome (839626938).

The spelling of 638610102 in words is "six hundred thirty-eight million, six hundred ten thousand, one hundred two".