163445921 has 2 divisors, whose sum is σ = 163445922. Its totient is φ = 163445920.

The previous prime is 163445911. The next prime is 163445927. The reversal of 163445921 is 129544361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 114725521 + 48720400 = 10711^2 + 6980^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-163445921 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (163445927) 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, 81722960 + 81722961.

It is an arithmetic number, because the mean of its divisors is an integer number (81722961).

Almost surely, 2^163445921 is an apocalyptic number.

It is an amenable number.

163445921 is a deficient number, since it is larger than the sum of its proper divisors (1).

163445921 is an equidigital number, since it uses as much as digits as its factorization.

163445921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 35.

The square root of 163445921 is about 12784.5970214160. The cubic root of 163445921 is about 546.7532361333.

The spelling of 163445921 in words is "one hundred sixty-three million, four hundred forty-five thousand, nine hundred twenty-one".