161019311 has 2 divisors, whose sum is σ = 161019312. Its totient is φ = 161019310.

The previous prime is 161019307. The next prime is 161019337. The reversal of 161019311 is 113910161.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161019311 - 2² = 161019307 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161019361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80509655 + 80509656.

It is an arithmetic number, because the mean of its divisors is an integer number (80509656).

Almost surely, 2^161019311 is an apocalyptic number.

161019311 is a deficient number, since it is larger than the sum of its proper divisors (1).

161019311 is an equidigital number, since it uses as much as digits as its factorization.

161019311 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 161019311 is about 12689.3384776355. The cubic root of 161019311 is about 544.0339320224.

Adding to 161019311 its reverse (113910161), we get a palindrome (274929472).

The spelling of 161019311 in words is "one hundred sixty-one million, nineteen thousand, three hundred eleven".