820630440 has 288 divisors, whose sum is σ = 3219259680. Its totient is φ = 187463808.

The previous prime is 820630423. The next prime is 820630451. The reversal of 820630440 is 44036028.

820630440 is a `hidden beast` number, since 8 + 20 + 630 + 4 + 4 + 0 = 666.

820630440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 475419 + ... + 477141.

It is an arithmetic number, because the mean of its divisors is an integer number (11177985).

Almost surely, 2^820630440 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 820630440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1609629840).

820630440 is an abundant number, since it is smaller than the sum of its proper divisors (2398629240).

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

820630440 is a wasteful number, since it uses less digits than its factorization.

820630440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1763 (or 1740 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 27.

The square root of 820630440 is about 28646.6479714469. The cubic root of 820630440 is about 936.2299730773.

Adding to 820630440 its reverse (44036028), we get a palindrome (864666468).

The spelling of 820630440 in words is "eight hundred twenty million, six hundred thirty thousand, four hundred forty".