161560091 has 8 divisors (see below), whose sum is σ = 201425664. Its totient is φ = 125890920.

The previous prime is 161560067. The next prime is 161560123. The reversal of 161560091 is 190065161.

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 161560091 - 2¹⁸ = 161297947 is a prime.

It is a super-2 number, since 2×161560091² = 52203326007856562, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161560031) by changing a digit.

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, 1049015 + ... + 1049168.

It is an arithmetic number, because the mean of its divisors is an integer number (25178208).

Almost surely, 2^161560091 is an apocalyptic number.

161560091 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

161560091 is a deficient number, since it is larger than the sum of its proper divisors (39865573).

161560091 is a wasteful number, since it uses less digits than its factorization.

161560091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2098201.

The product of its (nonzero) digits is 1620, while the sum is 29.

The square root of 161560091 is about 12710.6290560302. The cubic root of 161560091 is about 544.6422936804.

The spelling of 161560091 in words is "one hundred sixty-one million, five hundred sixty thousand, ninety-one".