1187129659981 has 2 divisors, whose sum is σ = 1187129659982. Its totient is φ = 1187129659980.

The previous prime is 1187129659949. The next prime is 1187129660009. The reversal of 1187129659981 is 1899569217811.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 649450633225 + 537679026756 = 805885^2 + 733266^2 .

It is a cyclic number.

It is not a de Polignac number, because 1187129659981 - 2⁵ = 1187129659949 is a prime.

It is a super-2 number, since 2×1187129659981² (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 (1187129659901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 593564829990 + 593564829991.

It is an arithmetic number, because the mean of its divisors is an integer number (593564829991).

Almost surely, 2^{1187129659981} is an apocalyptic number.

It is an amenable number.

1187129659981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1187129659981 is an equidigital number, since it uses as much as digits as its factorization.

1187129659981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 19595520, while the sum is 67.

The spelling of 1187129659981 in words is "one trillion, one hundred eighty-seven billion, one hundred twenty-nine million, six hundred fifty-nine thousand, nine hundred eighty-one".