648883891 has 4 divisors (see below), whose sum is σ = 650273832. Its totient is φ = 647493952.

The previous prime is 648883883. The next prime is 648883943. The reversal of 648883891 is 198388846.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 648883891 - 2³ = 648883883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (648880891) 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 3 ways as a sum of consecutive naturals, for example, 694270 + ... + 695203.

It is an arithmetic number, because the mean of its divisors is an integer number (162568458).

Almost surely, 2^648883891 is an apocalyptic number.

648883891 is a deficient number, since it is larger than the sum of its proper divisors (1389941).

648883891 is a wasteful number, since it uses less digits than its factorization.

648883891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1389940.

The product of its digits is 2654208, while the sum is 55.

The square root of 648883891 is about 25473.1994653204. The cubic root of 648883891 is about 865.7430175660.

The spelling of 648883891 in words is "six hundred forty-eight million, eight hundred eighty-three thousand, eight hundred ninety-one".