638155283700 has 576 divisors, whose sum is σ = 2285781700608. Its totient is φ = 135499161600.

The previous prime is 638155283687. The next prime is 638155283767. The reversal of 638155283700 is 7382551836.

It is a super-2 number, since 2×638155283700² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 638155283700.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 47734417 + ... + 47747783.

It is an arithmetic number, because the mean of its divisors is an integer number (3968371008).

Almost surely, 2^638155283700 is an apocalyptic number.

638155283700 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638155283700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1142890850304).

638155283700 is an abundant number, since it is smaller than the sum of its proper divisors (1647626416908).

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

638155283700 is a wasteful number, since it uses less digits than its factorization.

638155283700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13472 (or 13465 counting only the distinct ones).

The product of its (nonzero) digits is 1209600, while the sum is 48.

The spelling of 638155283700 in words is "six hundred thirty-eight billion, one hundred fifty-five million, two hundred eighty-three thousand, seven hundred".