1181065551 has 4 divisors (see below), whose sum is σ = 1574754072. Its totient is φ = 787377032.

The previous prime is 1181065541. The next prime is 1181065553. The reversal of 1181065551 is 1555601811.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1555601811 = 3 ⋅518533937.

It is a cyclic number.

It is not a de Polignac number, because 1181065551 - 2²⁶ = 1113956687 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1181065553) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 196844256 + ... + 196844261.

It is an arithmetic number, because the mean of its divisors is an integer number (393688518).

Almost surely, 2^1181065551 is an apocalyptic number.

1181065551 is a deficient number, since it is larger than the sum of its proper divisors (393688521).

1181065551 is an equidigital number, since it uses as much as digits as its factorization.

1181065551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 393688520.

The product of its (nonzero) digits is 6000, while the sum is 33.

The square root of 1181065551 is about 34366.6342693025. The cubic root of 1181065551 is about 1057.0397861117.

The spelling of 1181065551 in words is "one billion, one hundred eighty-one million, sixty-five thousand, five hundred fifty-one".