820220205 has 16 divisors (see below), whose sum is σ = 1499831424. Its totient is φ = 374957760.

The previous prime is 820220201. The next prime is 820220243. The reversal of 820220205 is 502022028.

It is not a de Polignac number, because 820220205 - 2² = 820220201 is a prime.

It is a super-2 number, since 2×820220205² = 1345522369380484050, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820220201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3905706 + ... + 3905915.

It is an arithmetic number, because the mean of its divisors is an integer number (93739464).

Almost surely, 2^820220205 is an apocalyptic number.

It is an amenable number.

820220205 is a deficient number, since it is larger than the sum of its proper divisors (679611219).

820220205 is a wasteful number, since it uses less digits than its factorization.

820220205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7811636.

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 820220205 is about 28639.4868145363. The cubic root of 820220205 is about 936.0739392518.

The spelling of 820220205 in words is "eight hundred twenty million, two hundred twenty thousand, two hundred five".