817869312 has 400 divisors, whose sum is σ = 2765807352. Its totient is φ = 238878720.

The previous prime is 817869293. The next prime is 817869317. The reversal of 817869312 is 213968718.

It can be written as a sum of positive squares in 4 ways, for example, as 524226816 + 293642496 = 22896^2 + 17136^2 .

It is a super-2 number, since 2×817869312² = 1337820423022706688, which contains 22 as substring.

Its product of digits (145152) is a multiple of the sum of its prime divisors (96).

It is not an unprimeable number, because it can be changed into a prime (817869317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 19948012 + ... + 19948052.

Almost surely, 2^817869312 is an apocalyptic number.

817869312 is a gapful number since it is divisible by the number (82) 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 817869312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1382903676).

817869312 is an abundant number, since it is smaller than the sum of its proper divisors (1947938040).

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

817869312 is a wasteful number, since it uses less digits than its factorization.

817869312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121 (or 96 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The square root of 817869312 is about 28598.4145015069. The cubic root of 817869312 is about 935.1787668519.

The spelling of 817869312 in words is "eight hundred seventeen million, eight hundred sixty-nine thousand, three hundred twelve".