161320231 has 2 divisors, whose sum is σ = 161320232. Its totient is φ = 161320230.

The previous prime is 161320223. The next prime is 161320253. The reversal of 161320231 is 132023161.

It is a weak prime.

It is an emirp because it is prime and its reverse (132023161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 161320231 - 2³ = 161320223 is a prime.

It is a super-2 number, since 2×161320231² = 52048433859786722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161320199 and 161320208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161320031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80660115 + 80660116.

It is an arithmetic number, because the mean of its divisors is an integer number (80660116).

Almost surely, 2^161320231 is an apocalyptic number.

161320231 is a deficient number, since it is larger than the sum of its proper divisors (1).

161320231 is an equidigital number, since it uses as much as digits as its factorization.

161320231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 161320231 is about 12701.1901410852. The cubic root of 161320231 is about 544.3726260012.

Adding to 161320231 its reverse (132023161), we get a palindrome (293343392).

The spelling of 161320231 in words is "one hundred sixty-one million, three hundred twenty thousand, two hundred thirty-one".