1191907531 has 2 divisors, whose sum is σ = 1191907532. Its totient is φ = 1191907530.

The previous prime is 1191907489. The next prime is 1191907559. The reversal of 1191907531 is 1357091911.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1191907531 - 2¹⁹ = 1191383243 is a prime.

It is a super-2 number, since 2×1191907531² = 2841287124909031922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1191907231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 595953765 + 595953766.

It is an arithmetic number, because the mean of its divisors is an integer number (595953766).

Almost surely, 2^1191907531 is an apocalyptic number.

1191907531 is a deficient number, since it is larger than the sum of its proper divisors (1).

1191907531 is an equidigital number, since it uses as much as digits as its factorization.

1191907531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8505, while the sum is 37.

The square root of 1191907531 is about 34524.0138309554. The cubic root of 1191907531 is about 1060.2644205060.

The spelling of 1191907531 in words is "one billion, one hundred ninety-one million, nine hundred seven thousand, five hundred thirty-one".