61561516616 has 32 divisors (see below), whose sum is σ = 116986464000. Its totient is φ = 30365776896.

The previous prime is 61561516591. The next prime is 61561516619. The reversal of 61561516616 is 61661516516.

It is not an unprimeable number, because it can be changed into a prime (61561516619) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 729125 + ... + 809163.

It is an arithmetic number, because the mean of its divisors is an integer number (3655827000).

Almost surely, 2^61561516616 is an apocalyptic number.

It is an amenable number.

61561516616 is a deficient number, since it is larger than the sum of its proper divisors (55424947384).

61561516616 is a wasteful number, since it uses less digits than its factorization.

61561516616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81341 (or 81337 counting only the distinct ones).

The product of its digits is 194400, while the sum is 44.

The spelling of 61561516616 in words is "sixty-one billion, five hundred sixty-one million, five hundred sixteen thousand, six hundred sixteen".