646809412 has 12 divisors (see below), whose sum is σ = 1132098940. Its totient is φ = 323352576.

The previous prime is 646809407. The next prime is 646809433. The reversal of 646809412 is 214908646.

It can be written as a sum of positive squares in 2 ways, for example, as 279090436 + 367718976 = 16706^2 + 19176^2 .

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 32764 + ... + 48652.

Almost surely, 2^646809412 is an apocalyptic number.

It is an amenable number.

646809412 is a deficient number, since it is larger than the sum of its proper divisors (485289528).

646809412 is a wasteful number, since it uses less digits than its factorization.

646809412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26070 (or 26068 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 40.

The square root of 646809412 is about 25432.4480142986. The cubic root of 646809412 is about 864.8194404109.

The spelling of 646809412 in words is "six hundred forty-six million, eight hundred nine thousand, four hundred twelve".