11001761561 has 4 divisors (see below), whose sum is σ = 12573441792. Its totient is φ = 9430081332.

The previous prime is 11001761513. The next prime is 11001761591. The reversal of 11001761561 is 16516710011.

11001761561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 16516710011 = 1153 ⋅14324987.

It is not a de Polignac number, because 11001761561 - 2²⁶ = 10934652697 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (11001761591) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 785840105 + ... + 785840118.

It is an arithmetic number, because the mean of its divisors is an integer number (3143360448).

Almost surely, 2^11001761561 is an apocalyptic number.

It is an amenable number.

11001761561 is a deficient number, since it is larger than the sum of its proper divisors (1571680231).

11001761561 is an equidigital number, since it uses as much as digits as its factorization.

11001761561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1571680230.

The product of its (nonzero) digits is 1260, while the sum is 29.

The spelling of 11001761561 in words is "eleven billion, one million, seven hundred sixty-one thousand, five hundred sixty-one".