11561236949 has 4 divisors (see below), whose sum is σ = 11843218380. Its totient is φ = 11279255520.

The previous prime is 11561236919. The next prime is 11561237027. The reversal of 11561236949 is 94963216511.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94963216511 = 113 ⋅840382447.

It can be written as a sum of positive squares in 2 ways, for example, as 6087900625 + 5473336324 = 78025^2 + 73982^2 .

It is a cyclic number.

It is not a de Polignac number, because 11561236949 - 2³² = 7266269653 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11561236919) 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, 140990654 + ... + 140990735.

It is an arithmetic number, because the mean of its divisors is an integer number (2960804595).

Almost surely, 2^11561236949 is an apocalyptic number.

It is an amenable number.

11561236949 is a deficient number, since it is larger than the sum of its proper divisors (281981431).

11561236949 is an equidigital number, since it uses as much as digits as its factorization.

11561236949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281981430.

The product of its digits is 349920, while the sum is 47.

The spelling of 11561236949 in words is "eleven billion, five hundred sixty-one million, two hundred thirty-six thousand, nine hundred forty-nine".