161561161661606 has 16 divisors (see below), whose sum is σ = 280073923909920. Its totient is φ = 68462514732480.

The previous prime is 161561161661579. The next prime is 161561161661657. The reversal of 161561161661606 is 606166161165161.

161561161661606 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×161561161661606² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 64831925585 + ... + 64831928076.

It is an arithmetic number, because the mean of its divisors is an integer number (17504620244370).

Almost surely, 2^{161561161661606} is an apocalyptic number.

161561161661606 is a deficient number, since it is larger than the sum of its proper divisors (118512762248314).

161561161661606 is a wasteful number, since it uses less digits than its factorization.

161561161661606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129663853759.

The product of its (nonzero) digits is 1399680, while the sum is 53.

The spelling of 161561161661606 in words is "one hundred sixty-one trillion, five hundred sixty-one billion, one hundred sixty-one million, six hundred sixty-one thousand, six hundred six".