1289842668 has 108 divisors (see below), whose sum is σ = 3517650864. Its totient is φ = 397742400.

The previous prime is 1289842627. The next prime is 1289842669. The reversal of 1289842668 is 8662489821.

1289842668 is a `hidden beast` number, since 128 + 98 + 426 + 6 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (1289842669) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 794898 + ... + 796518.

Almost surely, 2^1289842668 is an apocalyptic number.

1289842668 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 1289842668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1758825432).

1289842668 is an abundant number, since it is smaller than the sum of its proper divisors (2227808196).

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

1289842668 is a wasteful number, since it uses less digits than its factorization.

1289842668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1716 (or 1680 counting only the distinct ones).

The product of its digits is 2654208, while the sum is 54.

The square root of 1289842668 is about 35914.3796827956. The cubic root of 1289842668 is about 1088.5429759413.

The spelling of 1289842668 in words is "one billion, two hundred eighty-nine million, eight hundred forty-two thousand, six hundred sixty-eight".