1289260920 has 64 divisors (see below), whose sum is σ = 3933360000. Its totient is φ = 337973888.

The previous prime is 1289260919. The next prime is 1289260933. The reversal of 1289260920 is 290629821.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83970 + ... + 98129.

It is an arithmetic number, because the mean of its divisors is an integer number (61458750).

Almost surely, 2^1289260920 is an apocalyptic number.

1289260920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1289260920 is an abundant number, since it is smaller than the sum of its proper divisors (2644099080).

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

1289260920 is a wasteful number, since it uses less digits than its factorization.

1289260920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182172 (or 182168 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 39.

The square root of 1289260920 is about 35906.2796736170. The cubic root of 1289260920 is about 1088.3792988916.

The spelling of 1289260920 in words is "one billion, two hundred eighty-nine million, two hundred sixty thousand, nine hundred twenty".