61205210728 has 16 divisors (see below), whose sum is σ = 115040362500. Its totient is φ = 30527780736.

The previous prime is 61205210713. The next prime is 61205210797. The reversal of 61205210728 is 82701250216.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 48665242404 + 12539968324 = 220602^2 + 111982^2 .

It is a junction number, because it is equal to n+sod(n) for n = 61205210693 and 61205210702.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9349603 + ... + 9356146.

Almost surely, 2^61205210728 is an apocalyptic number.

It is an amenable number.

61205210728 is a deficient number, since it is larger than the sum of its proper divisors (53835151772).

61205210728 is a wasteful number, since it uses less digits than its factorization.

61205210728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18706164 (or 18706160 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 34.

The spelling of 61205210728 in words is "sixty-one billion, two hundred five million, two hundred ten thousand, seven hundred twenty-eight".