11637008981 has 4 divisors (see below), whose sum is σ = 12532163532. Its totient is φ = 10741854432.

The previous prime is 11637008947. The next prime is 11637008989. The reversal of 11637008981 is 18980073611.

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 2137582756 + 9499426225 = 46234^2 + 97465^2 .

It is a cyclic number.

It is not a de Polignac number, because 11637008981 - 2¹⁴ = 11636992597 is a prime.

It is a super-2 number, since 2×11637008981² (a number of 21 digits) 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 (11637008989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 447577256 + ... + 447577281.

It is an arithmetic number, because the mean of its divisors is an integer number (3133040883).

Almost surely, 2^11637008981 is an apocalyptic number.

It is an amenable number.

11637008981 is a deficient number, since it is larger than the sum of its proper divisors (895154551).

11637008981 is an equidigital number, since it uses as much as digits as its factorization.

11637008981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 895154550.

The product of its (nonzero) digits is 72576, while the sum is 44.

The spelling of 11637008981 in words is "eleven billion, six hundred thirty-seven million, eight thousand, nine hundred eighty-one".