1289808 has 90 divisors (see below), whose sum is σ = 3982446. Its totient is φ = 389376.

The previous prime is 1289803. The next prime is 1289831. The reversal of 1289808 is 8089821.

It can be written as a sum of positive squares in 3 ways, for example, as 17424 + 1272384 = 132^2 + 1128^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1289801) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 24310 + ... + 24362.

2^1289808 is an apocalyptic number.

1289808 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 1289808, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1991223).

1289808 is an abundant number, since it is smaller than the sum of its proper divisors (2692638).

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

1289808 is a wasteful number, since it uses less digits than its factorization.

1289808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93 (or 71 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 36.

The square root of 1289808 is about 1135.6971427278. The cubic root of 1289808 is about 108.8533223345.

The spelling of 1289808 in words is "one million, two hundred eighty-nine thousand, eight hundred eight".