1289871648 has 192 divisors, whose sum is σ = 4228519680. Its totient is φ = 379551744.

The previous prime is 1289871643. The next prime is 1289871683. The reversal of 1289871648 is 8461789821.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 1289871594 and 1289871603.

It is not an unprimeable number, because it can be changed into a prime (1289871643) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 255840 + ... + 260832.

It is an arithmetic number, because the mean of its divisors is an integer number (22023540).

Almost surely, 2^1289871648 is an apocalyptic number.

1289871648 is a gapful number since it is divisible by the number (18) 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 1289871648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2114259840).

1289871648 is an abundant number, since it is smaller than the sum of its proper divisors (2938648032).

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

1289871648 is a wasteful number, since it uses less digits than its factorization.

1289871648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5048 (or 5034 counting only the distinct ones).

The product of its digits is 1548288, while the sum is 54.

The square root of 1289871648 is about 35914.7831400943. The cubic root of 1289871648 is about 1088.5511282894.

The spelling of 1289871648 in words is "one billion, two hundred eighty-nine million, eight hundred seventy-one thousand, six hundred forty-eight".