646660967 has 4 divisors (see below), whose sum is σ = 646715616. Its totient is φ = 646606320.

The previous prime is 646660957. The next prime is 646660997. The reversal of 646660967 is 769066646.

It is a happy number.

646660967 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-646660967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646660957) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1334 + ... + 35987.

It is an arithmetic number, because the mean of its divisors is an integer number (161678904).

Almost surely, 2^646660967 is an apocalyptic number.

646660967 is a deficient number, since it is larger than the sum of its proper divisors (54649).

646660967 is a wasteful number, since it uses less digits than its factorization.

646660967 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54648.

The product of its (nonzero) digits is 1959552, while the sum is 50.

The square root of 646660967 is about 25429.5294293858. The cubic root of 646660967 is about 864.7532756634.

The spelling of 646660967 in words is "six hundred forty-six million, six hundred sixty thousand, nine hundred sixty-seven".