646385899 has 2 divisors, whose sum is σ = 646385900. Its totient is φ = 646385898.

The previous prime is 646385881. The next prime is 646385903. The reversal of 646385899 is 998583646.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 646385899 - 2⁷ = 646385771 is a prime.

It is not a weakly prime, because it can be changed into another prime (646385809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323192949 + 323192950.

It is an arithmetic number, because the mean of its divisors is an integer number (323192950).

Almost surely, 2^646385899 is an apocalyptic number.

646385899 is a deficient number, since it is larger than the sum of its proper divisors (1).

646385899 is an equidigital number, since it uses as much as digits as its factorization.

646385899 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11197440, while the sum is 58.

The square root of 646385899 is about 25424.1204174304. The cubic root of 646385899 is about 864.6306458771.

The spelling of 646385899 in words is "six hundred forty-six million, three hundred eighty-five thousand, eight hundred ninety-nine".