161103561 has 16 divisors (see below), whose sum is σ = 217311360. Its totient is φ = 106156800.

The previous prime is 161103557. The next prime is 161103583. The reversal of 161103561 is 165301161.

It is not a de Polignac number, because 161103561 - 2² = 161103557 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161103541) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 102961 + ... + 104513.

It is an arithmetic number, because the mean of its divisors is an integer number (13581960).

Almost surely, 2^161103561 is an apocalyptic number.

It is an amenable number.

161103561 is a deficient number, since it is larger than the sum of its proper divisors (56207799).

161103561 is a wasteful number, since it uses less digits than its factorization.

161103561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1936.

The product of its (nonzero) digits is 540, while the sum is 24.

The square root of 161103561 is about 12692.6577595081. The cubic root of 161103561 is about 544.1288002854.

The spelling of 161103561 in words is "one hundred sixty-one million, one hundred three thousand, five hundred sixty-one".