66563838 has 24 divisors (see below), whose sum is σ = 157333176. Its totient is φ = 20170800.

The previous prime is 66563807. The next prime is 66563867. The reversal of 66563838 is 83836566.

66563838 is a `hidden beast` number, since 6 + 6 + 5 + 638 + 3 + 8 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 66563793 and 66563802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 167893 + ... + 168288.

It is an arithmetic number, because the mean of its divisors is an integer number (6555549).

Almost surely, 2^66563838 is an apocalyptic number.

66563838 is an abundant number, since it is smaller than the sum of its proper divisors (90769338).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66563838 is a wasteful number, since it uses less digits than its factorization.

66563838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336200 (or 336197 counting only the distinct ones).

The product of its digits is 622080, while the sum is 45.

The square root of 66563838 is about 8158.6664351474. Note that the first 3 decimals coincide. The cubic root of 66563838 is about 405.2715508531.

It can be divided in two parts, 6 and 6563838, that added together give a square (6563844 = 2562²).

The spelling of 66563838 in words is "sixty-six million, five hundred sixty-three thousand, eight hundred thirty-eight".