161606506566165 has 64 divisors (see below), whose sum is σ = 261972166283520. Its totient is φ = 85061460787200.

The previous prime is 161606506566161. The next prime is 161606506566179. The reversal of 161606506566165 is 561665605606161.

It is not a de Polignac number, because 161606506566165 - 2² = 161606506566161 is a prime.

It is a super-2 number, since 2×161606506566165² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161606506566099 and 161606506566108.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161606506566161) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1069804890 + ... + 1069955940.

It is an arithmetic number, because the mean of its divisors is an integer number (4093315098180).

Almost surely, 2^{161606506566165} is an apocalyptic number.

161606506566165 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

161606506566165 is a deficient number, since it is larger than the sum of its proper divisors (100365659717355).

161606506566165 is a wasteful number, since it uses less digits than its factorization.

161606506566165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153222.

The product of its (nonzero) digits is 34992000, while the sum is 60.

The spelling of 161606506566165 in words is "one hundred sixty-one trillion, six hundred six billion, five hundred six million, five hundred sixty-six thousand, one hundred sixty-five".