66820016 has 20 divisors (see below), whose sum is σ = 129623400. Its totient is φ = 33368832.

The previous prime is 66820009. The next prime is 66820027. The reversal of 66820016 is 61002866.

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14075 + ... + 18213.

It is an arithmetic number, because the mean of its divisors is an integer number (6481170).

Almost surely, 2^66820016 is an apocalyptic number.

It is an amenable number.

66820016 is a deficient number, since it is larger than the sum of its proper divisors (62803384).

66820016 is a wasteful number, since it uses less digits than its factorization.

66820016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5156 (or 5150 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 66820016 is about 8174.3511057453. The cubic root of 66820016 is about 405.7907955008.

The spelling of 66820016 in words is "sixty-six million, eight hundred twenty thousand, sixteen".