61666666605 has 48 divisors (see below), whose sum is σ = 112673010240. Its totient is φ = 31999904064.

The previous prime is 61666666577. The next prime is 61666666613. The reversal of 61666666605 is 50666666616.

It is not a de Polignac number, because 61666666605 - 2⁵ = 61666666573 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 17982 + ... + 351648.

It is an arithmetic number, because the mean of its divisors is an integer number (2347354380).

Almost surely, 2^61666666605 is an apocalyptic number.

It is an amenable number.

61666666605 is a deficient number, since it is larger than the sum of its proper divisors (51006343635).

61666666605 is a wasteful number, since it uses less digits than its factorization.

61666666605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333755 (or 333712 counting only the distinct ones).

The product of its (nonzero) digits is 8398080, while the sum is 54.

It can be divided in two parts, 61 and 666666605, that added together give a palindrome (666666666).

The spelling of 61666666605 in words is "sixty-one billion, six hundred sixty-six million, six hundred sixty-six thousand, six hundred five".