820818120 has 64 divisors (see below), whose sum is σ = 2464499520. Its totient is φ = 218703104.

The previous prime is 820818091. The next prime is 820818133. The reversal of 820818120 is 21818028.

It is a super-2 number, since 2×820818120² = 1347484772240668800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 205987 + ... + 209933.

It is an arithmetic number, because the mean of its divisors is an integer number (38507805).

Almost surely, 2^820818120 is an apocalyptic number.

It is an amenable number.

820818120 is an abundant number, since it is smaller than the sum of its proper divisors (1643681400).

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

820818120 is a wasteful number, since it uses less digits than its factorization.

820818120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5694 (or 5690 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 30.

The square root of 820818120 is about 28649.9235601075. The cubic root of 820818120 is about 936.3013402601.

The spelling of 820818120 in words is "eight hundred twenty million, eight hundred eighteen thousand, one hundred twenty".