61100505561 has 8 divisors (see below), whose sum is σ = 82108816384. Its totient is φ = 40412932560.

The previous prime is 61100505547. The next prime is 61100505619. The reversal of 61100505561 is 16550500116.

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

It is not a de Polignac number, because 61100505561 - 2⁹ = 61100505049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61100505161) 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, 80184010 + ... + 80184771.

It is an arithmetic number, because the mean of its divisors is an integer number (10263602048).

Almost surely, 2^61100505561 is an apocalyptic number.

It is an amenable number.

61100505561 is a deficient number, since it is larger than the sum of its proper divisors (21008310823).

61100505561 is a wasteful number, since it uses less digits than its factorization.

61100505561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160368911.

The product of its (nonzero) digits is 4500, while the sum is 30.

The spelling of 61100505561 in words is "sixty-one billion, one hundred million, five hundred five thousand, five hundred sixty-one".