639788633378 has 16 divisors (see below), whose sum is σ = 976374056160. Its totient is φ = 314335340256.

The previous prime is 639788633371. The next prime is 639788633399. The reversal of 639788633378 is 873336887936.

It is not an unprimeable number, because it can be changed into a prime (639788633371) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 909176 + ... + 1451267.

It is an arithmetic number, because the mean of its divisors is an integer number (61023378510).

Almost surely, 2^639788633378 is an apocalyptic number.

639788633378 is a deficient number, since it is larger than the sum of its proper divisors (336585422782).

639788633378 is a wasteful number, since it uses less digits than its factorization.

639788633378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2362801.

The product of its digits is 658409472, while the sum is 71.

The spelling of 639788633378 in words is "six hundred thirty-nine billion, seven hundred eighty-eight million, six hundred thirty-three thousand, three hundred seventy-eight".