68078281 has 2 divisors, whose sum is σ = 68078282. Its totient is φ = 68078280.

The previous prime is 68078243. The next prime is 68078287. The reversal of 68078281 is 18287086.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64256256 + 3822025 = 8016^2 + 1955^2 .

It is a cyclic number.

It is not a de Polignac number, because 68078281 - 2¹¹ = 68076233 is a prime.

It is a super-2 number, since 2×68078281² = 9269304687829922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (68078287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34039140 + 34039141.

It is an arithmetic number, because the mean of its divisors is an integer number (34039141).

Almost surely, 2^68078281 is an apocalyptic number.

It is an amenable number.

68078281 is a deficient number, since it is larger than the sum of its proper divisors (1).

68078281 is an equidigital number, since it uses as much as digits as its factorization.

68078281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43008, while the sum is 40.

The square root of 68078281 is about 8250.9563688096. The cubic root of 68078281 is about 408.3220756395.

It can be divided in two parts, 680 and 78281, that added together give a square (78961 = 281²).

The spelling of 68078281 in words is "sixty-eight million, seventy-eight thousand, two hundred eighty-one".