161261105 has 8 divisors (see below), whose sum is σ = 193617000. Its totient is φ = 128939776.

The previous prime is 161261069. The next prime is 161261129. The reversal of 161261105 is 501162161.

It can be written as a sum of positive squares in 4 ways, for example, as 13808656 + 147452449 = 3716^2 + 12143^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161261105 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3071 + ... + 18219.

It is an arithmetic number, because the mean of its divisors is an integer number (24202125).

Almost surely, 2^161261105 is an apocalyptic number.

It is an amenable number.

161261105 is a deficient number, since it is larger than the sum of its proper divisors (32355895).

161261105 is a wasteful number, since it uses less digits than its factorization.

161261105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17283.

The product of its (nonzero) digits is 360, while the sum is 23.

The square root of 161261105 is about 12698.8623506202. The cubic root of 161261105 is about 544.3061112833.

The spelling of 161261105 in words is "one hundred sixty-one million, two hundred sixty-one thousand, one hundred five".