11131129981 has 2 divisors, whose sum is σ = 11131129982. Its totient is φ = 11131129980.

The previous prime is 11131129951. The next prime is 11131130033. The reversal of 11131129981 is 18992113111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7618671225 + 3512458756 = 87285^2 + 59266^2 .

It is a cyclic number.

It is not a de Polignac number, because 11131129981 - 2¹³ = 11131121789 is a prime.

It is a super-2 number, since 2×11131129981² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 11131129981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11131129951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5565564990 + 5565564991.

It is an arithmetic number, because the mean of its divisors is an integer number (5565564991).

Almost surely, 2^11131129981 is an apocalyptic number.

It is an amenable number.

11131129981 is a deficient number, since it is larger than the sum of its proper divisors (1).

11131129981 is an equidigital number, since it uses as much as digits as its factorization.

11131129981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 37.

The spelling of 11131129981 in words is "eleven billion, one hundred thirty-one million, one hundred twenty-nine thousand, nine hundred eighty-one".