162891881 has 2 divisors, whose sum is σ = 162891882. Its totient is φ = 162891880.

The previous prime is 162891857. The next prime is 162891901. The reversal of 162891881 is 188198261.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 145419481 + 17472400 = 12059^2 + 4180^2 .

It is an emirp because it is prime and its reverse (188198261) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-162891881 is a prime.

It is a super-2 number, since 2×162891881² = 53067529791436322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (162891481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81445940 + 81445941.

It is an arithmetic number, because the mean of its divisors is an integer number (81445941).

Almost surely, 2^162891881 is an apocalyptic number.

It is an amenable number.

162891881 is a deficient number, since it is larger than the sum of its proper divisors (1).

162891881 is an equidigital number, since it uses as much as digits as its factorization.

162891881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 55296, while the sum is 44.

The square root of 162891881 is about 12762.9103655867. The cubic root of 162891881 is about 546.1347520815.

The spelling of 162891881 in words is "one hundred sixty-two million, eight hundred ninety-one thousand, eight hundred eighty-one".