1191486251 has 2 divisors, whose sum is σ = 1191486252. Its totient is φ = 1191486250.

The previous prime is 1191486239. The next prime is 1191486253. The reversal of 1191486251 is 1526841911.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1191486251 is a prime.

Together with 1191486253, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1191486253) 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, 595743125 + 595743126.

It is an arithmetic number, because the mean of its divisors is an integer number (595743126).

Almost surely, 2^1191486251 is an apocalyptic number.

1191486251 is a deficient number, since it is larger than the sum of its proper divisors (1).

1191486251 is an equidigital number, since it uses as much as digits as its factorization.

1191486251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17280, while the sum is 38.

The square root of 1191486251 is about 34517.9120312918. The cubic root of 1191486251 is about 1060.1394888820.

The spelling of 1191486251 in words is "one billion, one hundred ninety-one million, four hundred eighty-six thousand, two hundred fifty-one".