1291899168 has 288 divisors, whose sum is σ = 4356084096. Its totient is φ = 355590144.

The previous prime is 1291899151. The next prime is 1291899187. The reversal of 1291899168 is 8619981921.

It is a tau number, because it is divible by the number of its divisors (288).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11432680 + ... + 11432792.

It is an arithmetic number, because the mean of its divisors is an integer number (15125292).

Almost surely, 2^1291899168 is an apocalyptic number.

1291899168 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 1291899168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2178042048).

1291899168 is an abundant number, since it is smaller than the sum of its proper divisors (3064184928).

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

1291899168 is a wasteful number, since it uses less digits than its factorization.

1291899168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296 (or 285 counting only the distinct ones).

The product of its digits is 559872, while the sum is 54.

The square root of 1291899168 is about 35942.9988732159. The cubic root of 1291899168 is about 1089.1211859865.

The spelling of 1291899168 in words is "one billion, two hundred ninety-one million, eight hundred ninety-nine thousand, one hundred sixty-eight".