68579561 has 4 divisors (see below), whose sum is σ = 68597124. Its totient is φ = 68562000.

The previous prime is 68579551. The next prime is 68579669. The reversal of 68579561 is 16597586.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 42823936 + 25755625 = 6544^2 + 5075^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68579561 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (68579521) 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, 11 + ... + 11711.

It is an arithmetic number, because the mean of its divisors is an integer number (17149281).

Almost surely, 2^68579561 is an apocalyptic number.

68579561 is the 3704-th centered decagonal number.

It is an amenable number.

68579561 is a deficient number, since it is larger than the sum of its proper divisors (17563).

68579561 is a wasteful number, since it uses less digits than its factorization.

68579561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17562.

The product of its digits is 453600, while the sum is 47.

The square root of 68579561 is about 8281.2777395762. The cubic root of 68579561 is about 409.3218235301.

The spelling of 68579561 in words is "sixty-eight million, five hundred seventy-nine thousand, five hundred sixty-one".