66811636 has 12 divisors (see below), whose sum is σ = 117231520. Its totient is φ = 33316920.

The previous prime is 66811631. The next prime is 66811651. The reversal of 66811636 is 63611866.

It is a happy number.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 66811595 and 66811604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66811631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20520 + ... + 23551.

Almost surely, 2^66811636 is an apocalyptic number.

It is an amenable number.

66811636 is a deficient number, since it is larger than the sum of its proper divisors (50419884).

66811636 is a wasteful number, since it uses less digits than its factorization.

66811636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44454 (or 44452 counting only the distinct ones).

The product of its digits is 31104, while the sum is 37.

The square root of 66811636 is about 8173.8385107610. The cubic root of 66811636 is about 405.7738311777.

The spelling of 66811636 in words is "sixty-six million, eight hundred eleven thousand, six hundred thirty-six".