66602220 has 96 divisors (see below), whose sum is σ = 201734400. Its totient is φ = 16360704.

The previous prime is 66602213. The next prime is 66602233. The reversal of 66602220 is 2220666.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 41391 + ... + 42969.

It is an arithmetic number, because the mean of its divisors is an integer number (2101400).

Almost surely, 2^66602220 is an apocalyptic number.

66602220 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 66602220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100867200).

66602220 is an abundant number, since it is smaller than the sum of its proper divisors (135132180).

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

66602220 is a wasteful number, since it uses less digits than its factorization.

66602220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1647 (or 1645 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 66602220 is about 8161.0183188129. The cubic root of 66602220 is about 405.3494316980.

Adding to 66602220 its reverse (2220666), we get a palindrome (68822886).

The spelling of 66602220 in words is "sixty-six million, six hundred two thousand, two hundred twenty".