6113581 has 4 divisors (see below), whose sum is σ = 6120252. Its totient is φ = 6106912.

The previous prime is 6113579. The next prime is 6113587. The reversal of 6113581 is 1853116.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 864900 + 5248681 = 930^2 + 2291^2 .

It is a cyclic number.

It is not a de Polignac number, because 6113581 - 2¹ = 6113579 is a prime.

It is a super-2 number, since 2×6113581² = 74751745287122, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6113587) 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, 1690 + ... + 3883.

It is an arithmetic number, because the mean of its divisors is an integer number (1530063).

Almost surely, 2^6113581 is an apocalyptic number.

It is an amenable number.

6113581 is a deficient number, since it is larger than the sum of its proper divisors (6671).

6113581 is a wasteful number, since it uses less digits than its factorization.

6113581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6670.

The product of its digits is 720, while the sum is 25.

The square root of 6113581 is about 2472.5656715242. The cubic root of 6113581 is about 182.8515124231.

Adding to 6113581 its reverse (1853116), we get a palindrome (7966697).

It can be divided in two parts, 61135 and 81, that added together give a palindrome (61216).

The spelling of 6113581 in words is "six million, one hundred thirteen thousand, five hundred eighty-one".