638475425280 has 720 divisors, whose sum is σ = 2806129641744. Its totient is φ = 132667637760.

The previous prime is 638475425267. The next prime is 638475425293. The reversal of 638475425280 is 82524574836.

638475425280 is a `hidden beast` number, since 6 + 3 + 8 + 4 + 75 + 42 + 528 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (638475425267) and next prime (638475425293).

It is a tau number, because it is divible by the number of its divisors (720).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 12392854 + ... + 12444266.

Almost surely, 2^638475425280 is an apocalyptic number.

638475425280 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 638475425280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1403064820872).

638475425280 is an abundant number, since it is smaller than the sum of its proper divisors (2167654216464).

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

638475425280 is a wasteful number, since it uses less digits than its factorization.

638475425280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51467 (or 51441 counting only the distinct ones).

The product of its (nonzero) digits is 12902400, while the sum is 54.

The spelling of 638475425280 in words is "six hundred thirty-eight billion, four hundred seventy-five million, four hundred twenty-five thousand, two hundred eighty".