1289121120 has 576 divisors, whose sum is σ = 5434490880. Its totient is φ = 271724544.

The previous prime is 1289121109. The next prime is 1289121121. The reversal of 1289121120 is 211219821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1289121121) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 10150497 + ... + 10150623.

It is an arithmetic number, because the mean of its divisors is an integer number (9434880).

Almost surely, 2^1289121120 is an apocalyptic number.

1289121120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1289121120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2717245440).

1289121120 is an abundant number, since it is smaller than the sum of its proper divisors (4145369760).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1289121120 is a wasteful number, since it uses less digits than its factorization.

1289121120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227 (or 216 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 27.

The square root of 1289121120 is about 35904.3328861573. The cubic root of 1289121120 is about 1088.3399582835.

The spelling of 1289121120 in words is "one billion, two hundred eighty-nine million, one hundred twenty-one thousand, one hundred twenty".