1181947489 has 2 divisors, whose sum is σ = 1181947490. Its totient is φ = 1181947488.

The previous prime is 1181947477. The next prime is 1181947513. The reversal of 1181947489 is 9847491811.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 774230625 + 407716864 = 27825^2 + 20192^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1181947489 is a prime.

It is not a weakly prime, because it can be changed into another prime (1181947439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 590973744 + 590973745.

It is an arithmetic number, because the mean of its divisors is an integer number (590973745).

Almost surely, 2^1181947489 is an apocalyptic number.

It is an amenable number.

1181947489 is a deficient number, since it is larger than the sum of its proper divisors (1).

1181947489 is an equidigital number, since it uses as much as digits as its factorization.

1181947489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 580608, while the sum is 52.

The square root of 1181947489 is about 34379.4631866177. The cubic root of 1181947489 is about 1057.3028286965.

The spelling of 1181947489 in words is "one billion, one hundred eighty-one million, nine hundred forty-seven thousand, four hundred eighty-nine".