638263262632 has 8 divisors (see below), whose sum is σ = 1196743617450. Its totient is φ = 319131631312.

The previous prime is 638263262573. The next prime is 638263262669. The reversal of 638263262632 is 236262362836.

It can be written as a sum of positive squares in only one way, i.e., 560782313316 + 77480949316 = 748854^2 + 278354^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39891453907 + ... + 39891453922.

Almost surely, 2^638263262632 is an apocalyptic number.

It is an amenable number.

638263262632 is a deficient number, since it is larger than the sum of its proper divisors (558480354818).

638263262632 is a wasteful number, since it uses less digits than its factorization.

638263262632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79782907835 (or 79782907831 counting only the distinct ones).

The product of its digits is 4478976, while the sum is 49.

The spelling of 638263262632 in words is "six hundred thirty-eight billion, two hundred sixty-three million, two hundred sixty-two thousand, six hundred thirty-two".