646728983 has 2 divisors, whose sum is σ = 646728984. Its totient is φ = 646728982.

The previous prime is 646728961. The next prime is 646728991. The reversal of 646728983 is 389827646.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 646728983 - 2¹⁰ = 646727959 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646728083) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323364491 + 323364492.

It is an arithmetic number, because the mean of its divisors is an integer number (323364492).

Almost surely, 2^646728983 is an apocalyptic number.

646728983 is a deficient number, since it is larger than the sum of its proper divisors (1).

646728983 is an equidigital number, since it uses as much as digits as its factorization.

646728983 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3483648, while the sum is 53.

The square root of 646728983 is about 25430.8667370973. The cubic root of 646728983 is about 864.7835929393.

The spelling of 646728983 in words is "six hundred forty-six million, seven hundred twenty-eight thousand, nine hundred eighty-three".