646500001949 has 2 divisors, whose sum is σ = 646500001950. Its totient is φ = 646500001948.

The previous prime is 646500001937. The next prime is 646500002021. The reversal of 646500001949 is 949100005646.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 642642722500 + 3857279449 = 801650^2 + 62107^2 .

It is a cyclic number.

It is not a de Polignac number, because 646500001949 - 2¹⁶ = 646499936413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646500001919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323250000974 + 323250000975.

It is an arithmetic number, because the mean of its divisors is an integer number (323250000975).

Almost surely, 2^646500001949 is an apocalyptic number.

It is an amenable number.

646500001949 is a deficient number, since it is larger than the sum of its proper divisors (1).

646500001949 is an equidigital number, since it uses as much as digits as its factorization.

646500001949 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 233280, while the sum is 44.

The spelling of 646500001949 in words is "six hundred forty-six billion, five hundred million, one thousand, nine hundred forty-nine".