1123100131981 has 2 divisors, whose sum is σ = 1123100131982. Its totient is φ = 1123100131980.

The previous prime is 1123100131969. The next prime is 1123100132009. The reversal of 1123100131981 is 1891310013211.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 798324380100 + 324775751881 = 893490^2 + 569891^2 .

It is an emirp because it is prime and its reverse (1891310013211) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1123100131981 is a prime.

It is a super-2 number, since 2×1123100131981² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1123100131961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 561550065990 + 561550065991.

It is an arithmetic number, because the mean of its divisors is an integer number (561550065991).

Almost surely, 2^{1123100131981} is an apocalyptic number.

It is an amenable number.

1123100131981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1123100131981 is an equidigital number, since it uses as much as digits as its factorization.

1123100131981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 31.

The spelling of 1123100131981 in words is "one trillion, one hundred twenty-three billion, one hundred million, one hundred thirty-one thousand, nine hundred eighty-one".