1288843920 has 640 divisors, whose sum is σ = 5599641600. Its totient is φ = 265254912.

The previous prime is 1288843883. The next prime is 1288843937. The reversal of 1288843920 is 293488821.

It is a super-2 number, since 2×1288843920² = 3322237300241932800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 15528199 + ... + 15528281.

It is an arithmetic number, because the mean of its divisors is an integer number (8749440).

Almost surely, 2^1288843920 is an apocalyptic number.

1288843920 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 1288843920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2799820800).

1288843920 is an abundant number, since it is smaller than the sum of its proper divisors (4310797680).

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

1288843920 is a wasteful number, since it uses less digits than its factorization.

1288843920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204 (or 192 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 45.

The square root of 1288843920 is about 35900.4724202900. The cubic root of 1288843920 is about 1088.2619440306.

The spelling of 1288843920 in words is "one billion, two hundred eighty-eight million, eight hundred forty-three thousand, nine hundred twenty".