161243021309041 has 64 divisors (see below), whose sum is σ = 199225732625920. Its totient is φ = 127436541788160.

The previous prime is 161243021308961. The next prime is 161243021309047. The reversal of 161243021309041 is 140903120342161.

It is a 5-Lehmer number, since φ(161243021309041) divides (161243021309041-1)⁵.

It is a cyclic number.

It is not a de Polignac number, because 161243021309041 - 2¹¹ = 161243021306993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161243021309047) 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, 5175826921 + ... + 5175858073.

It is an arithmetic number, because the mean of its divisors is an integer number (3112902072280).

It is a Poulet number, since it divides 2^{161243021309040}-1.

Almost surely, 2^{161243021309041} is an apocalyptic number.

161243021309041 is the 7331281-st hex number.

It is an amenable number.

161243021309041 is a deficient number, since it is larger than the sum of its proper divisors (37982711316879).

161243021309041 is a wasteful number, since it uses less digits than its factorization.

161243021309041 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37914.

The product of its (nonzero) digits is 31104, while the sum is 37.

The spelling of 161243021309041 in words is "one hundred sixty-one trillion, two hundred forty-three billion, twenty-one million, three hundred nine thousand, forty-one".