66546220 has 24 divisors (see below), whose sum is σ = 150497424. Its totient is φ = 24570816.

The previous prime is 66546187. The next prime is 66546223. The reversal of 66546220 is 2264566.

It is not an unprimeable number, because it can be changed into a prime (66546223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 127714 + ... + 128233.

It is an arithmetic number, because the mean of its divisors is an integer number (6270726).

Almost surely, 2^66546220 is an apocalyptic number.

It is an amenable number.

66546220 is an abundant number, since it is smaller than the sum of its proper divisors (83951204).

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

66546220 is a wasteful number, since it uses less digits than its factorization.

66546220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255969 (or 255967 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 66546220 is about 8157.5866529262. The cubic root of 66546220 is about 405.2357921768.

It can be divided in two parts, 66546 and 220, that added together give a palindrome (66766).

The spelling of 66546220 in words is "sixty-six million, five hundred forty-six thousand, two hundred twenty".