168280681 has 4 divisors (see below), whose sum is σ = 168387652. Its totient is φ = 168173712.

The previous prime is 168280667. The next prime is 168280771. The reversal of 168280681 is 186082861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 186082861 = 3989 ⋅46649.

It can be written as a sum of positive squares in 2 ways, for example, as 21483225 + 146797456 = 4635^2 + 12116^2 .

It is a cyclic number.

It is not a de Polignac number, because 168280681 - 2¹⁷ = 168149609 is a prime.

It is a super-2 number, since 2×168280681² = 56636775195647522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (168280621) 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, 51090 + ... + 54283.

It is an arithmetic number, because the mean of its divisors is an integer number (42096913).

Almost surely, 2^168280681 is an apocalyptic number.

It is an amenable number.

168280681 is a deficient number, since it is larger than the sum of its proper divisors (106971).

168280681 is a wasteful number, since it uses less digits than its factorization.

168280681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106970.

The product of its (nonzero) digits is 36864, while the sum is 40.

The square root of 168280681 is about 12972.3043827995. The cubic root of 168280681 is about 552.0919569986.

The spelling of 168280681 in words is "one hundred sixty-eight million, two hundred eighty thousand, six hundred eighty-one".