61891609436161 has 8 divisors (see below), whose sum is σ = 65486622477920. Its totient is φ = 58330352385792.

The previous prime is 61891609436093. The next prime is 61891609436171. The reversal of 61891609436161 is 16163490619816.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61891609436161 - 2³⁷ = 61754170482689 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 61891609436161.

It is not an unprimeable number, because it can be changed into a prime (61891609436171) 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, 8438994075 + ... + 8439001408.

It is an arithmetic number, because the mean of its divisors is an integer number (8185827809740).

Almost surely, 2^{61891609436161} is an apocalyptic number.

It is an amenable number.

61891609436161 is a deficient number, since it is larger than the sum of its proper divisors (3595013041759).

61891609436161 is a wasteful number, since it uses less digits than its factorization.

61891609436161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16877995695.

The product of its (nonzero) digits is 10077696, while the sum is 61.

The spelling of 61891609436161 in words is "sixty-one trillion, eight hundred ninety-one billion, six hundred nine million, four hundred thirty-six thousand, one hundred sixty-one".