1191425789991 has 32 divisors (see below), whose sum is σ = 1618151915520. Its totient is φ = 779630939136.

The previous prime is 1191425789987. The next prime is 1191425790001. The reversal of 1191425789991 is 1999875241911.

It is not a de Polignac number, because 1191425789991 - 2² = 1191425789987 is a prime.

It is a super-4 number, since 4×1191425789991⁴ (a number of 49 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1191425739991) 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 in 31 ways as a sum of consecutive naturals, for example, 208397665 + ... + 208403381.

It is an arithmetic number, because the mean of its divisors is an integer number (50567247360).

Almost surely, 2^{1191425789991} is an apocalyptic number.

1191425789991 is a deficient number, since it is larger than the sum of its proper divisors (426726125529).

1191425789991 is a wasteful number, since it uses less digits than its factorization.

1191425789991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11583.

The product of its digits is 14696640, while the sum is 66.

The spelling of 1191425789991 in words is "one trillion, one hundred ninety-one billion, four hundred twenty-five million, seven hundred eighty-nine thousand, nine hundred ninety-one".