113722561 has 4 divisors (see below), whose sum is σ = 116496324. Its totient is φ = 110948800.

The previous prime is 113722547. The next prime is 113722579. The reversal of 113722561 is 165227311.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 165227311 = 37 ⋅4465603.

It can be written as a sum of positive squares in 2 ways, for example, as 7529536 + 106193025 = 2744^2 + 10305^2 .

It is a cyclic number.

It is not a de Polignac number, because 113722561 - 2¹⁹ = 113198273 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (113722591) 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, 1386820 + ... + 1386901.

It is an arithmetic number, because the mean of its divisors is an integer number (29124081).

Almost surely, 2^113722561 is an apocalyptic number.

It is an amenable number.

113722561 is a deficient number, since it is larger than the sum of its proper divisors (2773763).

113722561 is an equidigital number, since it uses as much as digits as its factorization.

113722561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2773762.

The product of its digits is 2520, while the sum is 28.

The square root of 113722561 is about 10664.0780661059. The cubic root of 113722561 is about 484.4870915942.

Adding to 113722561 its reverse (165227311), we get a palindrome (278949872).

The spelling of 113722561 in words is "one hundred thirteen million, seven hundred twenty-two thousand, five hundred sixty-one".