161061655217 has 4 divisors (see below), whose sum is σ = 163791513840. Its totient is φ = 158331796596.

The previous prime is 161061655163. The next prime is 161061655241. The reversal of 161061655217 is 712556160161.

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: 712556160161 = 600979 ⋅1185659.

It is a cyclic number.

It is not a de Polignac number, because 161061655217 - 2²⁸ = 160793219761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161061655267) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1364929223 + ... + 1364929340.

It is an arithmetic number, because the mean of its divisors is an integer number (40947878460).

Almost surely, 2^161061655217 is an apocalyptic number.

It is an amenable number.

161061655217 is a deficient number, since it is larger than the sum of its proper divisors (2729858623).

161061655217 is an equidigital number, since it uses as much as digits as its factorization.

161061655217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2729858622.

The product of its (nonzero) digits is 75600, while the sum is 41.

The spelling of 161061655217 in words is "one hundred sixty-one billion, sixty-one million, six hundred fifty-five thousand, two hundred seventeen".