161156610561 has 8 divisors (see below), whose sum is σ = 216961650880. Its totient is φ = 106394655312.

The previous prime is 161156610547. The next prime is 161156610623. The reversal of 161156610561 is 165016651161.

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

It is not a de Polignac number, because 161156610561 - 2⁹ = 161156610049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161156610521) 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 7 ways as a sum of consecutive naturals, for example, 260770906 + ... + 260771523.

It is an arithmetic number, because the mean of its divisors is an integer number (27120206360).

Almost surely, 2^161156610561 is an apocalyptic number.

It is an amenable number.

161156610561 is a deficient number, since it is larger than the sum of its proper divisors (55805040319).

161156610561 is a wasteful number, since it uses less digits than its factorization.

161156610561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 521542535.

The product of its (nonzero) digits is 32400, while the sum is 39.

The spelling of 161156610561 in words is "one hundred sixty-one billion, one hundred fifty-six million, six hundred ten thousand, five hundred sixty-one".