168332981 has 4 divisors (see below), whose sum is σ = 168367212. Its totient is φ = 168298752.

The previous prime is 168332971. The next prime is 168332993. The reversal of 168332981 is 189233861.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 22648081 + 145684900 = 4759^2 + 12070^2 .

It is a cyclic number.

It is not a de Polignac number, because 168332981 - 2¹⁴ = 168316597 is a prime.

It is a super-2 number, since 2×168332981² = 56671984984692722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168332911) 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, 8186 + ... + 20091.

It is an arithmetic number, because the mean of its divisors is an integer number (42091803).

Almost surely, 2^168332981 is an apocalyptic number.

It is an amenable number.

168332981 is a deficient number, since it is larger than the sum of its proper divisors (34231).

168332981 is an equidigital number, since it uses as much as digits as its factorization.

168332981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34230.

The product of its digits is 62208, while the sum is 41.

The square root of 168332981 is about 12974.3200592555. The cubic root of 168332981 is about 552.1491460125.

The spelling of 168332981 in words is "one hundred sixty-eight million, three hundred thirty-two thousand, nine hundred eighty-one".