66617207220 has 48 divisors (see below), whose sum is σ = 191569488768. Its totient is φ = 17284464000.

The previous prime is 66617207207. The next prime is 66617207221. The reversal of 66617207220 is 2270271666.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66617207221) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 15001656 + ... + 15006095.

It is an arithmetic number, because the mean of its divisors is an integer number (3991031016).

Almost surely, 2^66617207220 is an apocalyptic number.

66617207220 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66617207220 is an abundant number, since it is smaller than the sum of its proper divisors (124952281548).

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

66617207220 is a wasteful number, since it uses less digits than its factorization.

66617207220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30007800 (or 30007798 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 39.

Adding to 66617207220 its reverse (2270271666), we get a palindrome (68887478886).

The spelling of 66617207220 in words is "sixty-six billion, six hundred seventeen million, two hundred seven thousand, two hundred twenty".