66650220 has 216 divisors, whose sum is σ = 250994016. Its totient is φ = 14017536.

The previous prime is 66650219. The next prime is 66650257. The reversal of 66650220 is 2205666.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 212784 + ... + 213096.

Almost surely, 2^66650220 is an apocalyptic number.

66650220 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66650220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125497008).

66650220 is an abundant number, since it is smaller than the sum of its proper divisors (184343796).

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

66650220 is a wasteful number, since it uses less digits than its factorization.

66650220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361 (or 343 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 66650220 is about 8163.9585986211. The cubic root of 66650220 is about 405.4467863129.

Adding to 66650220 its reverse (2205666), we get a palindrome (68855886).

The spelling of 66650220 in words is "sixty-six million, six hundred fifty thousand, two hundred twenty".