1191657149 has 2 divisors, whose sum is σ = 1191657150. Its totient is φ = 1191657148.

The previous prime is 1191657127. The next prime is 1191657193. The reversal of 1191657149 is 9417561911.

It is an a-pointer prime, because the next prime (1191657193) can be obtained adding 1191657149 to its sum of digits (44).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 811680100 + 379977049 = 28490^2 + 19493^2 .

It is an emirp because it is prime and its reverse (9417561911) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1191657149 - 2²⁴ = 1174879933 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1191657749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 595828574 + 595828575.

It is an arithmetic number, because the mean of its divisors is an integer number (595828575).

Almost surely, 2^1191657149 is an apocalyptic number.

It is an amenable number.

1191657149 is a deficient number, since it is larger than the sum of its proper divisors (1).

1191657149 is an equidigital number, since it uses as much as digits as its factorization.

1191657149 is an evil number, because the sum of its binary digits is even.

The product of its digits is 68040, while the sum is 44.

The square root of 1191657149 is about 34520.3874398883. The cubic root of 1191657149 is about 1060.1901726553.

The spelling of 1191657149 in words is "one billion, one hundred ninety-one million, six hundred fifty-seven thousand, one hundred forty-nine".