639809280000 has 2160 divisors, whose sum is σ = 2786958294120. Its totient is φ = 145981440000.

The previous prime is 639809279999. The next prime is 639809280001. The reversal of 639809280000 is 82908936.

639809280000 is a `hidden beast` number, since 639 + 8 + 0 + 9 + 2 + 8 + 0 + 0 + 0 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (639809279999) and next prime (639809280001).

It is a tau number, because it is divible by the number of its divisors (2160).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639809280001) by changing a digit.

It is a polite number, since it can be written in 179 ways as a sum of consecutive naturals, for example, 37635839992 + ... + 37635840008.

Almost surely, 2^639809280000 is an apocalyptic number.

639809280000 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 639809280000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1393479147060).

639809280000 is an abundant number, since it is smaller than the sum of its proper divisors (2147149014120).

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

639809280000 is an equidigital number, since it uses as much as digits as its factorization.

639809280000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96 (or 38 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 45.

The spelling of 639809280000 in words is "six hundred thirty-nine billion, eight hundred nine million, two hundred eighty thousand".