61665556 has 12 divisors (see below), whose sum is σ = 108031392. Its totient is φ = 30799448.

The previous prime is 61665533. The next prime is 61665557. The reversal of 61665556 is 65556616.

61665556 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61665557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3910 + ... + 11773.

It is an arithmetic number, because the mean of its divisors is an integer number (9002616).

Almost surely, 2^61665556 is an apocalyptic number.

It is an amenable number.

61665556 is a deficient number, since it is larger than the sum of its proper divisors (46365836).

61665556 is a wasteful number, since it uses less digits than its factorization.

61665556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16670 (or 16668 counting only the distinct ones).

The product of its digits is 162000, while the sum is 40.

The square root of 61665556 is about 7852.7419415132. The cubic root of 61665556 is about 395.0762145304.

The spelling of 61665556 in words is "sixty-one million, six hundred sixty-five thousand, five hundred fifty-six".