113556320561 has 2 divisors, whose sum is σ = 113556320562. Its totient is φ = 113556320560.

The previous prime is 113556320543. The next prime is 113556320617. The reversal of 113556320561 is 165023655311.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 102681793600 + 10874526961 = 320440^2 + 104281^2 .

It is an emirp because it is prime and its reverse (165023655311) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 113556320561 - 2¹⁰ = 113556319537 is a prime.

It is not a weakly prime, because it can be changed into another prime (113556326561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 56778160280 + 56778160281.

It is an arithmetic number, because the mean of its divisors is an integer number (56778160281).

Almost surely, 2^113556320561 is an apocalyptic number.

It is an amenable number.

113556320561 is a deficient number, since it is larger than the sum of its proper divisors (1).

113556320561 is an equidigital number, since it uses as much as digits as its factorization.

113556320561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 81000, while the sum is 38.

Adding to 113556320561 its reverse (165023655311), we get a palindrome (278579975872).

The spelling of 113556320561 in words is "one hundred thirteen billion, five hundred fifty-six million, three hundred twenty thousand, five hundred sixty-one".