1191280501 has 2 divisors, whose sum is σ = 1191280502. Its totient is φ = 1191280500.

The previous prime is 1191280483. The next prime is 1191280513. The reversal of 1191280501 is 1050821911.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1036775601 + 154504900 = 32199^2 + 12430^2 .

It is a cyclic number.

It is not a de Polignac number, because 1191280501 - 2¹¹ = 1191278453 is a prime.

It is a super-2 number, since 2×1191280501² = 2838298464125622002, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1191280501.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1191281501) 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, 595640250 + 595640251.

It is an arithmetic number, because the mean of its divisors is an integer number (595640251).

Almost surely, 2^1191280501 is an apocalyptic number.

It is an amenable number.

1191280501 is a deficient number, since it is larger than the sum of its proper divisors (1).

1191280501 is an equidigital number, since it uses as much as digits as its factorization.

1191280501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720, while the sum is 28.

The square root of 1191280501 is about 34514.9315659180. The cubic root of 1191280501 is about 1060.0784625081.

The spelling of 1191280501 in words is "one billion, one hundred ninety-one million, two hundred eighty thousand, five hundred one".