1116011581 has 4 divisors (see below), whose sum is σ = 1116085500. Its totient is φ = 1115937664.

The previous prime is 1116011579. The next prime is 1116011587. The reversal of 1116011581 is 1851106111.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1851106111 = 131 ⋅14130581.

It can be written as a sum of positive squares in 2 ways, for example, as 195860025 + 920151556 = 13995^2 + 30334^2 .

It is a cyclic number.

It is not a de Polignac number, because 1116011581 - 2¹ = 1116011579 is a prime.

It is a super-2 number, since 2×1116011581² = 2490963697852239122, 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 (1116011587) 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, 5236 + ... + 47533.

It is an arithmetic number, because the mean of its divisors is an integer number (279021375).

Almost surely, 2^1116011581 is an apocalyptic number.

It is an amenable number.

1116011581 is a deficient number, since it is larger than the sum of its proper divisors (73919).

1116011581 is an equidigital number, since it uses as much as digits as its factorization.

1116011581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73918.

The product of its (nonzero) digits is 240, while the sum is 25.

The square root of 1116011581 is about 33406.7595106140. The cubic root of 1116011581 is about 1037.2646254847.

Adding to 1116011581 its reverse (1851106111), we get a palindrome (2967117692).

The spelling of 1116011581 in words is "one billion, one hundred sixteen million, eleven thousand, five hundred eighty-one".