1268817816 has 128 divisors (see below), whose sum is σ = 3875558400. Its totient is φ = 338257920.

The previous prime is 1268817749. The next prime is 1268817821. The reversal of 1268817816 is 6187188621.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 154420 + ... + 162428.

It is an arithmetic number, because the mean of its divisors is an integer number (30277800).

Almost surely, 2^1268817816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1268817816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1937779200).

1268817816 is an abundant number, since it is smaller than the sum of its proper divisors (2606740584).

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

1268817816 is a wasteful number, since it uses less digits than its factorization.

1268817816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8089 (or 8085 counting only the distinct ones).

The product of its digits is 258048, while the sum is 48.

The square root of 1268817816 is about 35620.4690592362. The cubic root of 1268817816 is about 1082.5960114462.

The spelling of 1268817816 in words is "one billion, two hundred sixty-eight million, eight hundred seventeen thousand, eight hundred sixteen".