816865280 has 336 divisors, whose sum is σ = 2554961616. Its totient is φ = 247726080.

The previous prime is 816865267. The next prime is 816865307. The reversal of 816865280 is 82568618.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22077422 + ... + 22077458.

Almost surely, 2^816865280 is an apocalyptic number.

816865280 is a gapful number since it is divisible by the number (80) 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 816865280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1277480808).

816865280 is an abundant number, since it is smaller than the sum of its proper divisors (1738096336).

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

816865280 is a wasteful number, since it uses less digits than its factorization.

816865280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93 (or 62 counting only the distinct ones).

The product of its (nonzero) digits is 184320, while the sum is 44.

The square root of 816865280 is about 28580.8551306640. The cubic root of 816865280 is about 934.7959290398.

The spelling of 816865280 in words is "eight hundred sixteen million, eight hundred sixty-five thousand, two hundred eighty".