648792121 has 6 divisors (see below), whose sum is σ = 650497722. Its totient is φ = 647089200.

The previous prime is 648792103. The next prime is 648792167. The reversal of 648792121 is 121297846.

648792121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 621804096 + 26988025 = 24936^2 + 5195^2 .

It is a de Polignac number, because none of the positive numbers 2^k-648792121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (648792101) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 623920 + ... + 624958.

It is an arithmetic number, because the mean of its divisors is an integer number (108416287).

Almost surely, 2^648792121 is an apocalyptic number.

It is an amenable number.

648792121 is a deficient number, since it is larger than the sum of its proper divisors (1705601).

648792121 is an frugal number, since it uses more digits than its factorization.

648792121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2679 (or 1640 counting only the distinct ones).

The product of its digits is 48384, while the sum is 40.

The square root of 648792121 is about 25471.3980966888. The cubic root of 648792121 is about 865.7022023634.

The spelling of 648792121 in words is "six hundred forty-eight million, seven hundred ninety-two thousand, one hundred twenty-one".