163256381 has 2 divisors, whose sum is σ = 163256382. Its totient is φ = 163256380.

The previous prime is 163256371. The next prime is 163256407. The reversal of 163256381 is 183652361.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 152300281 + 10956100 = 12341^2 + 3310^2 .

It is an emirp because it is prime and its reverse (183652361) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-163256381 is a prime.

It is a super-2 number, since 2×163256381² = 53305291874434322, which contains 22 as substring.

It is a Chen prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (163256371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81628190 + 81628191.

It is an arithmetic number, because the mean of its divisors is an integer number (81628191).

Almost surely, 2^163256381 is an apocalyptic number.

It is an amenable number.

163256381 is a deficient number, since it is larger than the sum of its proper divisors (1).

163256381 is an equidigital number, since it uses as much as digits as its factorization.

163256381 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 163256381 is about 12777.1820445668. The cubic root of 163256381 is about 546.5418069903.

The spelling of 163256381 in words is "one hundred sixty-three million, two hundred fifty-six thousand, three hundred eighty-one".