161306231 has 2 divisors, whose sum is σ = 161306232. Its totient is φ = 161306230.

The previous prime is 161306221. The next prime is 161306269. The reversal of 161306231 is 132603161.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161306231 is a prime.

It is a super-2 number, since 2×161306231² = 52039400318850722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 161306197 and 161306206.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161306221) 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, 80653115 + 80653116.

It is an arithmetic number, because the mean of its divisors is an integer number (80653116).

Almost surely, 2^161306231 is an apocalyptic number.

161306231 is a deficient number, since it is larger than the sum of its proper divisors (1).

161306231 is an equidigital number, since it uses as much as digits as its factorization.

161306231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 161306231 is about 12700.6389996724. The cubic root of 161306231 is about 544.3568779511.

Adding to 161306231 its reverse (132603161), we get a palindrome (293909392).

The spelling of 161306231 in words is "one hundred sixty-one million, three hundred six thousand, two hundred thirty-one".