646271984 has 10 divisors (see below), whose sum is σ = 1252152000. Its totient is φ = 323135984.

The previous prime is 646271981. The next prime is 646271999. The reversal of 646271984 is 489172646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646271981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20195984 + ... + 20196015.

It is an arithmetic number, because the mean of its divisors is an integer number (125215200).

Almost surely, 2^646271984 is an apocalyptic number.

It is an amenable number.

646271984 is a deficient number, since it is larger than the sum of its proper divisors (605880016).

646271984 is a wasteful number, since it uses less digits than its factorization.

646271984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40392007 (or 40392001 counting only the distinct ones).

The product of its digits is 580608, while the sum is 47.

The square root of 646271984 is about 25421.8800248919. The cubic root of 646271984 is about 864.5798505308.

The spelling of 646271984 in words is "six hundred forty-six million, two hundred seventy-one thousand, nine hundred eighty-four".