1581443113 has 2 divisors, whose sum is σ = 1581443114. Its totient is φ = 1581443112.

The previous prime is 1581443111. The next prime is 1581443141. The reversal of 1581443113 is 3113441851.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1460156944 + 121286169 = 38212^2 + 11013^2 .

It is a cyclic number.

It is not a de Polignac number, because 1581443113 - 2¹ = 1581443111 is a prime.

It is a super-3 number, since 3×1581443113³ (a number of 29 digits) contains 333 as substring.

Together with 1581443111, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1581443111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 790721556 + 790721557.

It is an arithmetic number, because the mean of its divisors is an integer number (790721557).

Almost surely, 2^1581443113 is an apocalyptic number.

It is an amenable number.

1581443113 is a deficient number, since it is larger than the sum of its proper divisors (1).

1581443113 is an equidigital number, since it uses as much as digits as its factorization.

1581443113 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5760, while the sum is 31.

The square root of 1581443113 is about 39767.3624093930. The cubic root of 1581443113 is about 1165.0677784803.

Adding to 1581443113 its reverse (3113441851), we get a palindrome (4694884964).

The spelling of 1581443113 in words is "one billion, five hundred eighty-one million, four hundred forty-three thousand, one hundred thirteen".