61665225 has 24 divisors (see below), whose sum is σ = 104329632. Its totient is φ = 32121600.

The previous prime is 61665221. The next prime is 61665283. The reversal of 61665225 is 52256616.

It is a happy number.

It is not a de Polignac number, because 61665225 - 2² = 61665221 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61665221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6336 + ... + 12785.

It is an arithmetic number, because the mean of its divisors is an integer number (4347068).

Almost surely, 2^61665225 is an apocalyptic number.

It is an amenable number.

61665225 is a deficient number, since it is larger than the sum of its proper divisors (42664407).

61665225 is a wasteful number, since it uses less digits than its factorization.

61665225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19177 (or 19172 counting only the distinct ones).

The product of its digits is 21600, while the sum is 33.

The square root of 61665225 is about 7852.7208660438. The cubic root of 61665225 is about 395.0755076503.

The spelling of 61665225 in words is "sixty-one million, six hundred sixty-five thousand, two hundred twenty-five".