161606656010109 has 4 divisors (see below), whose sum is σ = 215475541346816. Its totient is φ = 107737770673404.

The previous prime is 161606656010083. The next prime is 161606656010243. The reversal of 161606656010109 is 901010656606161.

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.

It is not a de Polignac number, because 161606656010109 - 2⁹ = 161606656009597 is a prime.

It is a super-2 number, since 2×161606656010109² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161606656000109) 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, 26934442668349 + ... + 26934442668354.

It is an arithmetic number, because the mean of its divisors is an integer number (53868885336704).

Almost surely, 2^{161606656010109} is an apocalyptic number.

It is an amenable number.

161606656010109 is a deficient number, since it is larger than the sum of its proper divisors (53868885336707).

161606656010109 is an equidigital number, since it uses as much as digits as its factorization.

161606656010109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53868885336706.

The product of its (nonzero) digits is 349920, while the sum is 48.

The spelling of 161606656010109 in words is "one hundred sixty-one trillion, six hundred six billion, six hundred fifty-six million, ten thousand, one hundred nine".