68902809281 has 4 divisors (see below), whose sum is σ = 68903389632. Its totient is φ = 68902228932.

The previous prime is 68902809271. The next prime is 68902809299. The reversal of 68902809281 is 18290820986.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 18290820986 = 2 ⋅9145410493.

It is a cyclic number.

It is not a de Polignac number, because 68902809281 - 2³⁴ = 51722940097 is a prime.

It is a super-2 number, since 2×68902809281² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68902809211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40445 + ... + 373418.

It is an arithmetic number, because the mean of its divisors is an integer number (17225847408).

Almost surely, 2^68902809281 is an apocalyptic number.

It is an amenable number.

68902809281 is a deficient number, since it is larger than the sum of its proper divisors (580351).

68902809281 is a wasteful number, since it uses less digits than its factorization.

68902809281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 580350.

The product of its (nonzero) digits is 995328, while the sum is 53.

The spelling of 68902809281 in words is "sixty-eight billion, nine hundred two million, eight hundred nine thousand, two hundred eighty-one".