11461515581 has 2 divisors, whose sum is σ = 11461515582. Its totient is φ = 11461515580.

The previous prime is 11461515577. The next prime is 11461515607. The reversal of 11461515581 is 18551516411.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9683544025 + 1777971556 = 98405^2 + 42166^2 .

It is an emirp because it is prime and its reverse (18551516411) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11461515581 - 2² = 11461515577 is a prime.

It is a super-2 number, since 2×11461515581² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11461515511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5730757790 + 5730757791.

It is an arithmetic number, because the mean of its divisors is an integer number (5730757791).

Almost surely, 2^11461515581 is an apocalyptic number.

It is an amenable number.

11461515581 is a deficient number, since it is larger than the sum of its proper divisors (1).

11461515581 is an equidigital number, since it uses as much as digits as its factorization.

11461515581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24000, while the sum is 38.

The spelling of 11461515581 in words is "eleven billion, four hundred sixty-one million, five hundred fifteen thousand, five hundred eighty-one".