646922889 has 8 divisors (see below), whose sum is σ = 958404320. Its totient is φ = 431281908.

The previous prime is 646922867. The next prime is 646922891. The reversal of 646922889 is 988229646.

It is a happy number.

It is not a de Polignac number, because 646922889 - 2⁷ = 646922761 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (646922839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11980027 + ... + 11980080.

It is an arithmetic number, because the mean of its divisors is an integer number (119800540).

Almost surely, 2^646922889 is an apocalyptic number.

It is an amenable number.

646922889 is a deficient number, since it is larger than the sum of its proper divisors (311481431).

646922889 is a wasteful number, since it uses less digits than its factorization.

646922889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23960116 (or 23960110 counting only the distinct ones).

The product of its digits is 2985984, while the sum is 54.

The square root of 646922889 is about 25434.6788656747. The cubic root of 646922889 is about 864.8700124317.

The spelling of 646922889 in words is "six hundred forty-six million, nine hundred twenty-two thousand, eight hundred eighty-nine".