648191997797 has 8 divisors (see below), whose sum is σ = 648735859200. Its totient is φ = 647648339184.

The previous prime is 648191997793. The next prime is 648191997839. The reversal of 648191997797 is 797799191846.

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

It is a cyclic number.

It is not a de Polignac number, because 648191997797 - 2² = 648191997793 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648191997793) 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, 6718979 + ... + 6814767.

It is an arithmetic number, because the mean of its divisors is an integer number (81091982400).

Almost surely, 2^648191997797 is an apocalyptic number.

It is an amenable number.

648191997797 is a deficient number, since it is larger than the sum of its proper divisors (543861403).

648191997797 is a wasteful number, since it uses less digits than its factorization.

648191997797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101395.

The product of its digits is 432081216, while the sum is 77.

The spelling of 648191997797 in words is "six hundred forty-eight billion, one hundred ninety-one million, nine hundred ninety-seven thousand, seven hundred ninety-seven".