646712089 has 2 divisors, whose sum is σ = 646712090. Its totient is φ = 646712088.

The previous prime is 646712081. The next prime is 646712141. The reversal of 646712089 is 980217646.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 599858064 + 46854025 = 24492^2 + 6845^2 .

It is a cyclic number.

It is not a de Polignac number, because 646712089 - 2³ = 646712081 is a prime.

It is not a weakly prime, because it can be changed into another prime (646712081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323356044 + 323356045.

It is an arithmetic number, because the mean of its divisors is an integer number (323356045).

Almost surely, 2^646712089 is an apocalyptic number.

It is an amenable number.

646712089 is a deficient number, since it is larger than the sum of its proper divisors (1).

646712089 is an equidigital number, since it uses as much as digits as its factorization.

646712089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 145152, while the sum is 43.

The square root of 646712089 is about 25430.5345795168. The cubic root of 646712089 is about 864.7760628499.

The spelling of 646712089 in words is "six hundred forty-six million, seven hundred twelve thousand, eighty-nine".