163455821 has 2 divisors, whose sum is σ = 163455822. Its totient is φ = 163455820.

The previous prime is 163455797. The next prime is 163455827. The reversal of 163455821 is 128554361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 158482921 + 4972900 = 12589^2 + 2230^2 .

It is a cyclic number.

It is not a de Polignac number, because 163455821 - 2⁶ = 163455757 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (163455827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81727910 + 81727911.

It is an arithmetic number, because the mean of its divisors is an integer number (81727911).

Almost surely, 2^163455821 is an apocalyptic number.

It is an amenable number.

163455821 is a deficient number, since it is larger than the sum of its proper divisors (1).

163455821 is an equidigital number, since it uses as much as digits as its factorization.

163455821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28800, while the sum is 35.

The square root of 163455821 is about 12784.9842002249. The cubic root of 163455821 is about 546.7642749481.

The spelling of 163455821 in words is "one hundred sixty-three million, four hundred fifty-five thousand, eight hundred twenty-one".