646870039 has 2 divisors, whose sum is σ = 646870040. Its totient is φ = 646870038.

The previous prime is 646870033. The next prime is 646870051. The reversal of 646870039 is 930078646.

It is a happy number.

646870039 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 646870039 - 2¹⁵ = 646837271 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 646869977 and 646870004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646870033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323435019 + 323435020.

It is an arithmetic number, because the mean of its divisors is an integer number (323435020).

Almost surely, 2^646870039 is an apocalyptic number.

646870039 is a deficient number, since it is larger than the sum of its proper divisors (1).

646870039 is an equidigital number, since it uses as much as digits as its factorization.

646870039 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 217728, while the sum is 43.

The square root of 646870039 is about 25433.6399085935. The cubic root of 646870039 is about 864.8464601013.

The spelling of 646870039 in words is "six hundred forty-six million, eight hundred seventy thousand, thirty-nine".