161266993 has 2 divisors, whose sum is σ = 161266994. Its totient is φ = 161266992.

The previous prime is 161266921. The next prime is 161267023. The reversal of 161266993 is 399662161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 136585969 + 24681024 = 11687^2 + 4968^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161266993 is a prime.

It is not a weakly prime, because it can be changed into another prime (161266393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80633496 + 80633497.

It is an arithmetic number, because the mean of its divisors is an integer number (80633497).

Almost surely, 2^161266993 is an apocalyptic number.

It is an amenable number.

161266993 is a deficient number, since it is larger than the sum of its proper divisors (1).

161266993 is an equidigital number, since it uses as much as digits as its factorization.

161266993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 104976, while the sum is 43.

The square root of 161266993 is about 12699.0941802949. The cubic root of 161266993 is about 544.3127358098.

The spelling of 161266993 in words is "one hundred sixty-one million, two hundred sixty-six thousand, nine hundred ninety-three".