68027816561 has 4 divisors (see below), whose sum is σ = 68157889392. Its totient is φ = 67897743732.

The previous prime is 68027816551. The next prime is 68027816567. The reversal of 68027816561 is 16561872086.

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.

It is a cyclic number.

It is not a de Polignac number, because 68027816561 - 2¹⁸ = 68027554417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68027816567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65035631 + ... + 65036676.

It is an arithmetic number, because the mean of its divisors is an integer number (17039472348).

Almost surely, 2^68027816561 is an apocalyptic number.

It is an amenable number.

68027816561 is a deficient number, since it is larger than the sum of its proper divisors (130072831).

68027816561 is a wasteful number, since it uses less digits than its factorization.

68027816561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130072830.

The product of its (nonzero) digits is 967680, while the sum is 50.

The spelling of 68027816561 in words is "sixty-eight billion, twenty-seven million, eight hundred sixteen thousand, five hundred sixty-one".