638156574748 has 192 divisors, whose sum is σ = 1485761937408. Its totient is φ = 232186567680.

The previous prime is 638156574661. The next prime is 638156574827. The reversal of 638156574748 is 847475651836.

It is a super-2 number, since 2×638156574748² (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 638156574748.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 447200811 + ... + 447202237.

It is an arithmetic number, because the mean of its divisors is an integer number (7738343424).

Almost surely, 2^638156574748 is an apocalyptic number.

638156574748 is a gapful number since it is divisible by the number (68) 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 638156574748, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (742880968704).

638156574748 is an abundant number, since it is smaller than the sum of its proper divisors (847605362660).

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

638156574748 is a wasteful number, since it uses less digits than its factorization.

638156574748 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2072 (or 2070 counting only the distinct ones).

The product of its digits is 135475200, while the sum is 64.

The spelling of 638156574748 in words is "six hundred thirty-eight billion, one hundred fifty-six million, five hundred seventy-four thousand, seven hundred forty-eight".