161859280541 has 4 divisors (see below), whose sum is σ = 184982034912. Its totient is φ = 138736526172.

The previous prime is 161859280501. The next prime is 161859280547. The reversal of 161859280541 is 145082958161.

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 a cyclic number.

It is not a de Polignac number, because 161859280541 - 2⁶ = 161859280477 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161859280541.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161859280547) 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, 11561377175 + ... + 11561377188.

It is an arithmetic number, because the mean of its divisors is an integer number (46245508728).

Almost surely, 2^161859280541 is an apocalyptic number.

It is an amenable number.

161859280541 is a deficient number, since it is larger than the sum of its proper divisors (23122754371).

161859280541 is an equidigital number, since it uses as much as digits as its factorization.

161859280541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23122754370.

The product of its (nonzero) digits is 691200, while the sum is 50.

The spelling of 161859280541 in words is "one hundred sixty-one billion, eight hundred fifty-nine million, two hundred eighty thousand, five hundred forty-one".