161161106566 has 4 divisors (see below), whose sum is σ = 241741659852. Its totient is φ = 80580553282.

The previous prime is 161161106549. The next prime is 161161106597. The reversal of 161161106566 is 665601161161.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40290276640 + ... + 40290276643.

It is an arithmetic number, because the mean of its divisors is an integer number (60435414963).

Almost surely, 2^161161106566 is an apocalyptic number.

161161106566 is a deficient number, since it is larger than the sum of its proper divisors (80580553286).

161161106566 is an equidigital number, since it uses as much as digits as its factorization.

161161106566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80580553285.

The product of its (nonzero) digits is 38880, while the sum is 40.

The spelling of 161161106566 in words is "one hundred sixty-one billion, one hundred sixty-one million, one hundred six thousand, five hundred sixty-six".