66866616 has 24 divisors (see below), whose sum is σ = 181097280. Its totient is φ = 22288848.

The previous prime is 66866599. The next prime is 66866621. The reversal of 66866616 is 61666866.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×66866616² = 8942288670582912, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 464280 + ... + 464423.

It is an arithmetic number, because the mean of its divisors is an integer number (7545720).

Almost surely, 2^66866616 is an apocalyptic number.

It is an amenable number.

66866616 is an abundant number, since it is smaller than the sum of its proper divisors (114230664).

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

66866616 is a wasteful number, since it uses less digits than its factorization.

66866616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 928715 (or 928708 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The square root of 66866616 is about 8177.2009881132. The cubic root of 66866616 is about 405.8851058489.

The spelling of 66866616 in words is "sixty-six million, eight hundred sixty-six thousand, six hundred sixteen".