1166531251 has 4 divisors (see below), whose sum is σ = 1166684400. Its totient is φ = 1166378104.

The previous prime is 1166531237. The next prime is 1166531257. The reversal of 1166531251 is 1521356611.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1521356611 = 347 ⋅4384313.

It is a cyclic number.

It is not a de Polignac number, because 1166531251 - 2⁷ = 1166531123 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1166531257) 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 3 ways as a sum of consecutive naturals, for example, 64516 + ... + 80593.

It is an arithmetic number, because the mean of its divisors is an integer number (291671100).

Almost surely, 2^1166531251 is an apocalyptic number.

1166531251 is a deficient number, since it is larger than the sum of its proper divisors (153149).

1166531251 is an equidigital number, since it uses as much as digits as its factorization.

1166531251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153148.

The product of its digits is 5400, while the sum is 31.

The square root of 1166531251 is about 34154.5202132895. The cubic root of 1166531251 is about 1052.6858678408.

Adding to 1166531251 its reverse (1521356611), we get a palindrome (2687887862).

The spelling of 1166531251 in words is "one billion, one hundred sixty-six million, five hundred thirty-one thousand, two hundred fifty-one".