61666568 has 16 divisors (see below), whose sum is σ = 118750380. Its totient is φ = 29999808.

The previous prime is 61666559. The next prime is 61666573. The reversal of 61666568 is 86566616.

61666568 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 61434244 + 232324 = 7838^2 + 482^2 .

It is an unprimeable number.

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, 103871 + ... + 104462.

Almost surely, 2^61666568 is an apocalyptic number.

It is an amenable number.

61666568 is a deficient number, since it is larger than the sum of its proper divisors (57083812).

61666568 is a wasteful number, since it uses less digits than its factorization.

61666568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208376 (or 208372 counting only the distinct ones).

The product of its digits is 311040, while the sum is 44.

The square root of 61666568 is about 7852.8063773405. The cubic root of 61666568 is about 395.0783757311.

The spelling of 61666568 in words is "sixty-one million, six hundred sixty-six thousand, five hundred sixty-eight".