161193811 has 2 divisors, whose sum is σ = 161193812. Its totient is φ = 161193810.

The previous prime is 161193763. The next prime is 161193817. The reversal of 161193811 is 118391161.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 161193811 - 2¹⁵ = 161161043 is a prime.

It is not a weakly prime, because it can be changed into another prime (161193817) 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, 80596905 + 80596906.

It is an arithmetic number, because the mean of its divisors is an integer number (80596906).

Almost surely, 2^161193811 is an apocalyptic number.

161193811 is a deficient number, since it is larger than the sum of its proper divisors (1).

161193811 is an equidigital number, since it uses as much as digits as its factorization.

161193811 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 31.

The square root of 161193811 is about 12696.2124667162. The cubic root of 161193811 is about 544.2303880607.

The spelling of 161193811 in words is "one hundred sixty-one million, one hundred ninety-three thousand, eight hundred eleven".