268651681 has 2 divisors, whose sum is σ = 268651682. Its totient is φ = 268651680.

The previous prime is 268651651. The next prime is 268651687. The reversal of 268651681 is 186156862.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 268435456 + 216225 = 16384^2 + 465^2 .

It is a cyclic number.

It is not a de Polignac number, because 268651681 - 2⁷ = 268651553 is a prime.

It is a super-3 number, since 3×268651681³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (268651687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 134325840 + 134325841.

It is an arithmetic number, because the mean of its divisors is an integer number (134325841).

Almost surely, 2^268651681 is an apocalyptic number.

It is an amenable number.

268651681 is a deficient number, since it is larger than the sum of its proper divisors (1).

268651681 is an equidigital number, since it uses as much as digits as its factorization.

268651681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 138240, while the sum is 43.

The square root of 268651681 is about 16390.5973350577. The cubic root of 268651681 is about 645.2527351206.

The spelling of 268651681 in words is "two hundred sixty-eight million, six hundred fifty-one thousand, six hundred eighty-one".