66420216 has 96 divisors (see below), whose sum is σ = 190203600. Its totient is φ = 21470400.

The previous prime is 66420187. The next prime is 66420223. The reversal of 66420216 is 61202466.

It is a happy number.

66420216 is a `hidden beast` number, since 6 + 642 + 0 + 2 + 16 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 66420216.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 935461 + ... + 935531.

Almost surely, 2^66420216 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66420216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95101800).

66420216 is an abundant number, since it is smaller than the sum of its proper divisors (123783384).

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

66420216 is a wasteful number, since it uses less digits than its factorization.

66420216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218 (or 137 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 66420216 is about 8149.8598760960. The cubic root of 66420216 is about 404.9798618245.

The spelling of 66420216 in words is "sixty-six million, four hundred twenty thousand, two hundred sixteen".