66544225 has 12 divisors (see below), whose sum is σ = 90016560. Its totient is φ = 48395600.

The previous prime is 66544223. The next prime is 66544237. The reversal of 66544225 is 52244566.

It is not a de Polignac number, because 66544225 - 2¹ = 66544223 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66544223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 120715 + ... + 121264.

It is an arithmetic number, because the mean of its divisors is an integer number (7501380).

Almost surely, 2^66544225 is an apocalyptic number.

It is an amenable number.

66544225 is a deficient number, since it is larger than the sum of its proper divisors (23472335).

66544225 is a wasteful number, since it uses less digits than its factorization.

66544225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242000 (or 241995 counting only the distinct ones).

The product of its digits is 57600, while the sum is 34.

The square root of 66544225 is about 8157.4643731983. The cubic root of 66544225 is about 405.2317425930.

The spelling of 66544225 in words is "sixty-six million, five hundred forty-four thousand, two hundred twenty-five".