161441631889 has 4 divisors (see below), whose sum is σ = 161450864640. Its totient is φ = 161432399140.

The previous prime is 161441631881. The next prime is 161441631907. The reversal of 161441631889 is 988136144161.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 988136144161 = 433 ⋅2282069617.

It is a cyclic number.

It is not a de Polignac number, because 161441631889 - 2³ = 161441631881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161441631881) 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, 4590097 + ... + 4625134.

It is an arithmetic number, because the mean of its divisors is an integer number (40362716160).

Almost surely, 2^161441631889 is an apocalyptic number.

It is an amenable number.

161441631889 is a deficient number, since it is larger than the sum of its proper divisors (9232751).

161441631889 is an equidigital number, since it uses as much as digits as its factorization.

161441631889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9232750.

The product of its digits is 995328, while the sum is 52.

The spelling of 161441631889 in words is "one hundred sixty-one billion, four hundred forty-one million, six hundred thirty-one thousand, eight hundred eighty-nine".