161101191 has 4 divisors (see below), whose sum is σ = 214801592. Its totient is φ = 107400792.

The previous prime is 161101169. The next prime is 161101217. The reversal of 161101191 is 191101161.

161101191 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 191101161 = 3 ⋅63700387.

It is not a de Polignac number, because 161101191 - 2⁵ = 161101159 is a prime.

161101191 is a strobogrammatic number because it is the same when read upside-down.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161101111) 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, 26850196 + ... + 26850201.

It is an arithmetic number, because the mean of its divisors is an integer number (53700398).

Almost surely, 2^161101191 is an apocalyptic number.

161101191 is a deficient number, since it is larger than the sum of its proper divisors (53700401).

161101191 is an equidigital number, since it uses as much as digits as its factorization.

161101191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53700400.

The product of its (nonzero) digits is 54, while the sum is 21.

The square root of 161101191 is about 12692.5643981033. The cubic root of 161101191 is about 544.1261320398.

The spelling of 161101191 in words is "one hundred sixty-one million, one hundred one thousand, one hundred ninety-one".