13061581 has 4 divisors (see below), whose sum is σ = 14066332. Its totient is φ = 12056832.

The previous prime is 13061561. The next prime is 13061599. The reversal of 13061581 is 18516031.

13061581 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 6604900 + 6456681 = 2570^2 + 2541^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13061581 is a prime.

It is a super-2 number, since 2×13061581² = 341209796439122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13061561) 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, 502356 + ... + 502381.

It is an arithmetic number, because the mean of its divisors is an integer number (3516583).

Almost surely, 2^13061581 is an apocalyptic number.

It is an amenable number.

13061581 is a deficient number, since it is larger than the sum of its proper divisors (1004751).

13061581 is a wasteful number, since it uses less digits than its factorization.

13061581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1004750.

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

The square root of 13061581 is about 3614.0809343455. The cubic root of 13061581 is about 235.5041598128.

The spelling of 13061581 in words is "thirteen million, sixty-one thousand, five hundred eighty-one".