66613225 has 24 divisors (see below), whose sum is σ = 99957888. Its totient is φ = 42988800.

The previous prime is 66613223. The next prime is 66613229. The reversal of 66613225 is 52231666.

It is not a de Polignac number, because 66613225 - 2¹ = 66613223 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66613223) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8221 + ... + 14170.

It is an arithmetic number, because the mean of its divisors is an integer number (4164912).

Almost surely, 2^66613225 is an apocalyptic number.

It is an amenable number.

66613225 is a deficient number, since it is larger than the sum of its proper divisors (33344663).

66613225 is a wasteful number, since it uses less digits than its factorization.

66613225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22425 (or 22420 counting only the distinct ones).

The product of its digits is 12960, while the sum is 31.

The square root of 66613225 is about 8161.6925328022. The cubic root of 66613225 is about 405.3717564034.

The spelling of 66613225 in words is "sixty-six million, six hundred thirteen thousand, two hundred twenty-five".