220220820 has 36 divisors (see below), whose sum is σ = 668003700. Its totient is φ = 58725504.

The previous prime is 220220813. The next prime is 220220821. The reversal of 220220820 is 28022022.

It can be written as a sum of positive squares in 2 ways, for example, as 48191364 + 172029456 = 6942^2 + 13116^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×220220820² = 96994419122944800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 220220793 and 220220802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (220220821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 611545 + ... + 611904.

Almost surely, 2^220220820 is an apocalyptic number.

220220820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

220220820 is an abundant number, since it is smaller than the sum of its proper divisors (447782880).

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

220220820 is a wasteful number, since it uses less digits than its factorization.

220220820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1223464 (or 1223459 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 220220820 is about 14839.8389479131. The cubic root of 220220820 is about 603.8829831934.

Adding to 220220820 its reverse (28022022), we get a palindrome (248242842).

The spelling of 220220820 in words is "two hundred twenty million, two hundred twenty thousand, eight hundred twenty".