68887729 has 2 divisors, whose sum is σ = 68887730. Its totient is φ = 68887728.

The previous prime is 68887699. The next prime is 68887733. The reversal of 68887729 is 92778886.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42928704 + 25959025 = 6552^2 + 5095^2 .

It is a cyclic number.

It is not a de Polignac number, because 68887729 - 2⁷ = 68887601 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 68887729.

It is not a weakly prime, because it can be changed into another prime (68887769) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34443864 + 34443865.

It is an arithmetic number, because the mean of its divisors is an integer number (34443865).

Almost surely, 2^68887729 is an apocalyptic number.

It is an amenable number.

68887729 is a deficient number, since it is larger than the sum of its proper divisors (1).

68887729 is an equidigital number, since it uses as much as digits as its factorization.

68887729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2709504, while the sum is 55.

The square root of 68887729 is about 8299.8631916436. The cubic root of 68887729 is about 409.9340147626.

Subtracting from 68887729 its product of digits (2709504), we obtain a square (66178225 = 8135²).

The spelling of 68887729 in words is "sixty-eight million, eight hundred eighty-seven thousand, seven hundred twenty-nine".