647644372 has 6 divisors (see below), whose sum is σ = 1133377658. Its totient is φ = 323822184.

The previous prime is 647644339. The next prime is 647644379. The reversal of 647644372 is 273446746.

It can be written as a sum of positive squares in only one way, i.e., 376515216 + 271129156 = 19404^2 + 16466^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647644379) 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 as a sum of consecutive naturals, namely, 80955543 + ... + 80955550.

Almost surely, 2^647644372 is an apocalyptic number.

It is an amenable number.

647644372 is a deficient number, since it is larger than the sum of its proper divisors (485733286).

647644372 is a wasteful number, since it uses less digits than its factorization.

647644372 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161911097 (or 161911095 counting only the distinct ones).

The product of its digits is 677376, while the sum is 43.

The square root of 647644372 is about 25448.8579704473. The cubic root of 647644372 is about 865.1914094105.

The spelling of 647644372 in words is "six hundred forty-seven million, six hundred forty-four thousand, three hundred seventy-two".