66816832 has 28 divisors (see below), whose sum is σ = 133103620. Its totient is φ = 33278976.

The previous prime is 66816829. The next prime is 66816833. The reversal of 66816832 is 23861866.

It can be written as a sum of positive squares in 2 ways, for example, as 33454656 + 33362176 = 5784^2 + 5776^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66816833) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15844 + ... + 19612.

Almost surely, 2^66816832 is an apocalyptic number.

It is an amenable number.

66816832 is a deficient number, since it is larger than the sum of its proper divisors (66286788).

66816832 is a wasteful number, since it uses less digits than its factorization.

66816832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4058 (or 4048 counting only the distinct ones).

The product of its digits is 82944, while the sum is 40.

The square root of 66816832 is about 8174.1563479053. The cubic root of 66816832 is about 405.7843500349.

It can be divided in two parts, 668168 and 32, that multiplied together give a 4-th power (21381376 = 68⁴).

The spelling of 66816832 in words is "sixty-six million, eight hundred sixteen thousand, eight hundred thirty-two".