638701332480 has 576 divisors, whose sum is σ = 2320940381760. Its totient is φ = 162260582400.

The previous prime is 638701332449. The next prime is 638701332509. The reversal of 638701332480 is 84233107836.

638701332480 is a `hidden beast` number, since 6 + 38 + 7 + 0 + 133 + 2 + 480 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

It is a super-2 number, since 2×638701332480² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 162476115 + ... + 162480045.

It is an arithmetic number, because the mean of its divisors is an integer number (4029410385).

Almost surely, 2^638701332480 is an apocalyptic number.

638701332480 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 638701332480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1160470190880).

638701332480 is an abundant number, since it is smaller than the sum of its proper divisors (1682239049280).

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

638701332480 is a wasteful number, since it uses less digits than its factorization.

638701332480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4048 (or 4025 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 45.

The spelling of 638701332480 in words is "six hundred thirty-eight billion, seven hundred one million, three hundred thirty-two thousand, four hundred eighty".