61863773661 has 6 divisors (see below), whose sum is σ = 89358784190. Its totient is φ = 41242515768.

The previous prime is 61863773651. The next prime is 61863773669. The reversal of 61863773661 is 16637736816.

It is a happy number.

61863773661 is a `hidden beast` number, since 6 + 186 + 377 + 36 + 61 = 666.

It can be written as a sum of positive squares in only one way, i.e., 55988551161 + 5875222500 = 236619^2 + 76650^2 .

It is not a de Polignac number, because 61863773661 - 2¹⁰ = 61863772637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61863773598 and 61863773607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61863773669) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3436876306 + ... + 3436876323.

Almost surely, 2^61863773661 is an apocalyptic number.

It is an amenable number.

61863773661 is a deficient number, since it is larger than the sum of its proper divisors (27495010529).

61863773661 is a wasteful number, since it uses less digits than its factorization.

61863773661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6873752635 (or 6873752632 counting only the distinct ones).

The product of its digits is 4572288, while the sum is 54.

The spelling of 61863773661 in words is "sixty-one billion, eight hundred sixty-three million, seven hundred seventy-three thousand, six hundred sixty-one".