68281809 has 16 divisors (see below), whose sum is σ = 99509760. Its totient is φ = 41460480.

The previous prime is 68281799. The next prime is 68281819. The reversal of 68281809 is 90818286.

It is an interprime number because it is at equal distance from previous prime (68281799) and next prime (68281819).

It is not a de Polignac number, because 68281809 - 2⁴ = 68281793 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (68281819) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20014 + ... + 23175.

It is an arithmetic number, because the mean of its divisors is an integer number (6219360).

Almost surely, 2^68281809 is an apocalyptic number.

It is an amenable number.

68281809 is a deficient number, since it is larger than the sum of its proper divisors (31227951).

68281809 is a wasteful number, since it uses less digits than its factorization.

68281809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43240.

The product of its (nonzero) digits is 55296, while the sum is 42.

The square root of 68281809 is about 8263.2807649262. The cubic root of 68281809 is about 408.7285797115.

The spelling of 68281809 in words is "sixty-eight million, two hundred eighty-one thousand, eight hundred nine".