639657420801 has 8 divisors (see below), whose sum is σ = 974716069824. Its totient is φ = 365518526160.

The previous prime is 639657420791. The next prime is 639657420821. The reversal of 639657420801 is 108024756936.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 639657420801 - 2⁹ = 639657420289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (639657420821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15229938570 + ... + 15229938611.

It is an arithmetic number, because the mean of its divisors is an integer number (121839508728).

It is a 1-persistent number, because it is pandigital, but 2⋅639657420801 = 1279314841602 is not.

Almost surely, 2^639657420801 is an apocalyptic number.

It is an amenable number.

639657420801 is a deficient number, since it is larger than the sum of its proper divisors (335058649023).

639657420801 is a wasteful number, since it uses less digits than its factorization.

639657420801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30459877191.

The product of its (nonzero) digits is 2177280, while the sum is 51.

The spelling of 639657420801 in words is "six hundred thirty-nine billion, six hundred fifty-seven million, four hundred twenty thousand, eight hundred one".