161606155016605 has 8 divisors (see below), whose sum is σ = 208844877252312. Its totient is φ = 119339929858368.

The previous prime is 161606155016587. The next prime is 161606155016611. The reversal of 161606155016605 is 506610551606161.

It can be written as a sum of positive squares in 4 ways, for example, as 1210743714244 + 160395411302361 = 1100338^2 + 12664731^2 .

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 161606155016605 - 2⁵ = 161606155016573 is a prime.

It is a super-2 number, since 2×161606155016605² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1243124269294 + ... + 1243124269423.

It is an arithmetic number, because the mean of its divisors is an integer number (26105609656539).

Almost surely, 2^{161606155016605} is an apocalyptic number.

It is an amenable number.

161606155016605 is a deficient number, since it is larger than the sum of its proper divisors (47238722235707).

161606155016605 is a wasteful number, since it uses less digits than its factorization.

161606155016605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2486248538735.

The product of its (nonzero) digits is 972000, while the sum is 49.

The spelling of 161606155016605 in words is "one hundred sixty-one trillion, six hundred six billion, one hundred fifty-five million, sixteen thousand, six hundred five".