639142560 has 288 divisors, whose sum is σ = 2514395520. Its totient is φ = 144820224.

The previous prime is 639142549. The next prime is 639142573. The reversal of 639142560 is 65241936.

It is a happy number.

639142560 is a `hidden beast` number, since 6 + 3 + 91 + 4 + 2 + 560 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

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

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, 1642846 + ... + 1643234.

It is an arithmetic number, because the mean of its divisors is an integer number (8730540).

Almost surely, 2^639142560 is an apocalyptic number.

639142560 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 639142560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1257197760).

639142560 is an abundant number, since it is smaller than the sum of its proper divisors (1875252960).

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

639142560 is a wasteful number, since it uses less digits than its factorization.

639142560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 580 (or 569 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 639142560 is about 25281.2689554935. The cubic root of 639142560 is about 861.3888501653.

The spelling of 639142560 in words is "six hundred thirty-nine million, one hundred forty-two thousand, five hundred sixty".