638734132 has 24 divisors (see below), whose sum is σ = 1196846280. Its totient is φ = 297200640.

The previous prime is 638734097. The next prime is 638734171. The reversal of 638734132 is 231437836.

It can be written as a sum of positive squares in 4 ways, for example, as 211237156 + 427496976 = 14534^2 + 20676^2 .

It is a junction number, because it is equal to n+sod(n) for n = 638734091 and 638734100.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 46719 + ... + 58822.

It is an arithmetic number, because the mean of its divisors is an integer number (49868595).

Almost surely, 2^638734132 is an apocalyptic number.

It is an amenable number.

638734132 is a deficient number, since it is larger than the sum of its proper divisors (558112148).

638734132 is a wasteful number, since it uses less digits than its factorization.

638734132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105651 (or 105649 counting only the distinct ones).

The product of its digits is 72576, while the sum is 37.

The square root of 638734132 is about 25273.1899846458. The cubic root of 638734132 is about 861.2053280981.

The spelling of 638734132 in words is "six hundred thirty-eight million, seven hundred thirty-four thousand, one hundred thirty-two".