1291544989 has 24 divisors (see below), whose sum is σ = 1525916448. Its totient is φ = 1089819360.

The previous prime is 1291544983. The next prime is 1291545001. The reversal of 1291544989 is 9894451921.

It is not a de Polignac number, because 1291544989 - 2⁹ = 1291544477 is a prime.

It is a super-2 number, since 2×1291544989² = 3336176917222020242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1291544983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2199954 + ... + 2200540.

It is an arithmetic number, because the mean of its divisors is an integer number (63579852).

Almost surely, 2^1291544989 is an apocalyptic number.

It is an amenable number.

1291544989 is a deficient number, since it is larger than the sum of its proper divisors (234371459).

1291544989 is an equidigital number, since it uses as much as digits as its factorization.

1291544989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1225 (or 1218 counting only the distinct ones).

The product of its digits is 933120, while the sum is 52.

The square root of 1291544989 is about 35938.0715815415. The cubic root of 1291544989 is about 1089.0216480044.

The spelling of 1291544989 in words is "one billion, two hundred ninety-one million, five hundred forty-four thousand, nine hundred eighty-nine".