646439272 has 16 divisors (see below), whose sum is σ = 1216686240. Its totient is φ = 321989616.

The previous prime is 646439267. The next prime is 646439293. The reversal of 646439272 is 272934646.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 151518 + ... + 155725.

It is an arithmetic number, because the mean of its divisors is an integer number (76042890).

Almost surely, 2^646439272 is an apocalyptic number.

It is an amenable number.

646439272 is a deficient number, since it is larger than the sum of its proper divisors (570246968).

646439272 is a wasteful number, since it uses less digits than its factorization.

646439272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307512 (or 307508 counting only the distinct ones).

The product of its digits is 435456, while the sum is 43.

The square root of 646439272 is about 25425.1700485955. The cubic root of 646439272 is about 864.6544431481.

The spelling of 646439272 in words is "six hundred forty-six million, four hundred thirty-nine thousand, two hundred seventy-two".