648447931 has 2 divisors, whose sum is σ = 648447932. Its totient is φ = 648447930.

The previous prime is 648447929. The next prime is 648448013. The reversal of 648447931 is 139744846.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 648447931 - 2¹ = 648447929 is a prime.

It is a super-2 number, since 2×648447931² = 840969438436361522, which contains 22 as substring.

Together with 648447929, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (648447131) 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 as a sum of consecutive naturals, namely, 324223965 + 324223966.

It is an arithmetic number, because the mean of its divisors is an integer number (324223966).

Almost surely, 2^648447931 is an apocalyptic number.

648447931 is a deficient number, since it is larger than the sum of its proper divisors (1).

648447931 is an equidigital number, since it uses as much as digits as its factorization.

648447931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 580608, while the sum is 46.

The square root of 648447931 is about 25464.6407985662. The cubic root of 648447931 is about 865.5490877071.

The spelling of 648447931 in words is "six hundred forty-eight million, four hundred forty-seven thousand, nine hundred thirty-one".