161133311 has 4 divisors (see below), whose sum is σ = 161204712. Its totient is φ = 161061912.

The previous prime is 161133277. The next prime is 161133337. The reversal of 161133311 is 113331161.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 161133311 - 2¹⁴ = 161116927 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161133211) 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, 32201 + ... + 36866.

It is an arithmetic number, because the mean of its divisors is an integer number (40301178).

Almost surely, 2^161133311 is an apocalyptic number.

161133311 is a deficient number, since it is larger than the sum of its proper divisors (71401).

161133311 is an equidigital number, since it uses as much as digits as its factorization.

161133311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71400.

The product of its digits is 162, while the sum is 20.

The square root of 161133311 is about 12693.8296427831. The cubic root of 161133311 is about 544.1622918593.

Adding to 161133311 its reverse (113331161), we get a palindrome (274464472).

The spelling of 161133311 in words is "one hundred sixty-one million, one hundred thirty-three thousand, three hundred eleven".