61665606642 has 16 divisors (see below), whose sum is σ = 130585990752. Its totient is φ = 19346072640.

The previous prime is 61665606637. The next prime is 61665606671. The reversal of 61665606642 is 24660656616.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 61665606591 and 61665606600.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 302282284 + ... + 302282487.

It is an arithmetic number, because the mean of its divisors is an integer number (8161624422).

Almost surely, 2^61665606642 is an apocalyptic number.

61665606642 is an abundant number, since it is smaller than the sum of its proper divisors (68920384110).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61665606642 is a wasteful number, since it uses less digits than its factorization.

61665606642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 604564793.

The product of its (nonzero) digits is 1866240, while the sum is 48.

The spelling of 61665606642 in words is "sixty-one billion, six hundred sixty-five million, six hundred six thousand, six hundred forty-two".