161650161555661 has 8 divisors (see below), whose sum is σ = 162248962658048. Its totient is φ = 161051377410000.

The previous prime is 161650161555637. The next prime is 161650161555689. The reversal of 161650161555661 is 166555161056161.

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 161650161555661 - 2⁹ = 161650161555149 is a prime.

It is a super-2 number, since 2×161650161555661² (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 (161650161556661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15024151 + ... + 23431291.

It is an arithmetic number, because the mean of its divisors is an integer number (20281120332256).

Almost surely, 2^{161650161555661} is an apocalyptic number.

It is an amenable number.

161650161555661 is a deficient number, since it is larger than the sum of its proper divisors (598801102387).

161650161555661 is an equidigital number, since it uses as much as digits as its factorization.

161650161555661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8478363.

The product of its (nonzero) digits is 4860000, while the sum is 55.

The spelling of 161650161555661 in words is "one hundred sixty-one trillion, six hundred fifty billion, one hundred sixty-one million, five hundred fifty-five thousand, six hundred sixty-one".