163478891 has 2 divisors, whose sum is σ = 163478892. Its totient is φ = 163478890.

The previous prime is 163478863. The next prime is 163478893. The reversal of 163478891 is 198874361.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-163478891 is a prime.

It is a Sophie Germain prime.

Together with 163478893, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (163478893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81739445 + 81739446.

It is an arithmetic number, because the mean of its divisors is an integer number (81739446).

Almost surely, 2^163478891 is an apocalyptic number.

163478891 is a deficient number, since it is larger than the sum of its proper divisors (1).

163478891 is an equidigital number, since it uses as much as digits as its factorization.

163478891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 290304, while the sum is 47.

The square root of 163478891 is about 12785.8863986819. The cubic root of 163478891 is about 546.7899970022.

The spelling of 163478891 in words is "one hundred sixty-three million, four hundred seventy-eight thousand, eight hundred ninety-one".