168998881 has 4 divisors (see below), whose sum is σ = 169149700. Its totient is φ = 168848064.

The previous prime is 168998867. The next prime is 168998909. The reversal of 168998881 is 188899861.

168998881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 188899861 = 1693 ⋅111577.

It can be written as a sum of positive squares in 2 ways, for example, as 4928400 + 164070481 = 2220^2 + 12809^2 .

It is a cyclic number.

It is not a de Polignac number, because 168998881 - 2²³ = 160610273 is a prime.

It is a super-2 number, since 2×168998881² = 57121243558504322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (168998381) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 73716 + ... + 75973.

It is an arithmetic number, because the mean of its divisors is an integer number (42287425).

Almost surely, 2^168998881 is an apocalyptic number.

It is an amenable number.

168998881 is a deficient number, since it is larger than the sum of its proper divisors (150819).

168998881 is a wasteful number, since it uses less digits than its factorization.

168998881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150818.

The product of its digits is 1990656, while the sum is 58.

The square root of 168998881 is about 12999.9569614672. The cubic root of 168998881 is about 552.8762611090.

The spelling of 168998881 in words is "one hundred sixty-eight million, nine hundred ninety-eight thousand, eight hundred eighty-one".