820756800 has 252 divisors, whose sum is σ = 3026639616. Its totient is φ = 218764800.

The previous prime is 820756799. The next prime is 820756879. The reversal of 820756800 is 8657028.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 387745 + ... + 389855.

Almost surely, 2^820756800 is an apocalyptic number.

820756800 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 820756800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1513319808).

820756800 is an abundant number, since it is smaller than the sum of its proper divisors (2205882816).

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

820756800 is a wasteful number, since it uses less digits than its factorization.

820756800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2148 (or 2121 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 820756800 is about 28648.8533801966. The cubic root of 820756800 is about 936.2780239181.

The spelling of 820756800 in words is "eight hundred twenty million, seven hundred fifty-six thousand, eight hundred".