638124480 has 280 divisors, whose sum is σ = 2594933088. Its totient is φ = 145815552.

The previous prime is 638124479. The next prime is 638124511. The reversal of 638124480 is 84421836.

638124480 is a `hidden beast` number, since 638 + 12 + 4 + 4 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (280).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 179682 + ... + 183198.

Almost surely, 2^638124480 is an apocalyptic number.

638124480 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 638124480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1297466544).

638124480 is an abundant number, since it is smaller than the sum of its proper divisors (1956808608).

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

638124480 is a wasteful number, since it uses less digits than its factorization.

638124480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3553 (or 3534 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 36.

The square root of 638124480 is about 25261.1258656458. The cubic root of 638124480 is about 860.9312429160.

The spelling of 638124480 in words is "six hundred thirty-eight million, one hundred twenty-four thousand, four hundred eighty".