68756561 has 4 divisors (see below), whose sum is σ = 68835312. Its totient is φ = 68677812.

The previous prime is 68756557. The next prime is 68756587. The reversal of 68756561 is 16565786.

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 68756561 - 2² = 68756557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68756521) 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, 38051 + ... + 39816.

It is an arithmetic number, because the mean of its divisors is an integer number (17208828).

Almost surely, 2^68756561 is an apocalyptic number.

It is an amenable number.

68756561 is a deficient number, since it is larger than the sum of its proper divisors (78751).

68756561 is an equidigital number, since it uses as much as digits as its factorization.

68756561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78750.

The product of its digits is 302400, while the sum is 44.

The square root of 68756561 is about 8291.9576096360. The cubic root of 68756561 is about 409.6736665630.

The spelling of 68756561 in words is "sixty-eight million, seven hundred fifty-six thousand, five hundred sixty-one".