1199531491 has 2 divisors, whose sum is σ = 1199531492. Its totient is φ = 1199531490.

The previous prime is 1199531423. The next prime is 1199531519. The reversal of 1199531491 is 1941359911.

It is a strong prime.

It is an emirp because it is prime and its reverse (1941359911) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1199531491 - 2⁹ = 1199530979 is a prime.

It is not a weakly prime, because it can be changed into another prime (1199531591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 599765745 + 599765746.

It is an arithmetic number, because the mean of its divisors is an integer number (599765746).

Almost surely, 2^1199531491 is an apocalyptic number.

1199531491 is a deficient number, since it is larger than the sum of its proper divisors (1).

1199531491 is an equidigital number, since it uses as much as digits as its factorization.

1199531491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43740, while the sum is 43.

The square root of 1199531491 is about 34634.2531462713. The cubic root of 1199531491 is about 1062.5202553186.

The spelling of 1199531491 in words is "one billion, one hundred ninety-nine million, five hundred thirty-one thousand, four hundred ninety-one".