638613620646 has 16 divisors (see below), whose sum is σ = 1285799238000. Its totient is φ = 211442540768.

The previous prime is 638613620633. The next prime is 638613620677. The reversal of 638613620646 is 646026316836.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 357165561 + ... + 357167348.

It is an arithmetic number, because the mean of its divisors is an integer number (80362452375).

Almost surely, 2^638613620646 is an apocalyptic number.

638613620646 is an abundant number, since it is smaller than the sum of its proper divisors (647185617354).

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

638613620646 is a wasteful number, since it uses less digits than its factorization.

638613620646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 714333063.

The product of its (nonzero) digits is 4478976, while the sum is 51.

The spelling of 638613620646 in words is "six hundred thirty-eight billion, six hundred thirteen million, six hundred twenty thousand, six hundred forty-six".