1101021220 has 24 divisors (see below), whose sum is σ = 2490002424. Its totient is φ = 406530816.

The previous prime is 1101021217. The next prime is 1101021223. The reversal of 1101021220 is 221201011.

It is an interprime number because it is at equal distance from previous prime (1101021217) and next prime (1101021223).

It can be written as a sum of positive squares in 4 ways, for example, as 146458404 + 954562816 = 12102^2 + 30896^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 1101021197 and 1101021206.

It is not an unprimeable number, because it can be changed into a prime (1101021223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2117089 + ... + 2117608.

It is an arithmetic number, because the mean of its divisors is an integer number (103750101).

Almost surely, 2^1101021220 is an apocalyptic number.

1101021220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1101021220 is an abundant number, since it is smaller than the sum of its proper divisors (1388981204).

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

1101021220 is a wasteful number, since it uses less digits than its factorization.

1101021220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4234719 (or 4234717 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 1101021220 is about 33181.6398027584. The cubic root of 1101021220 is about 1032.5994666803.

Adding to 1101021220 its reverse (221201011), we get a palindrome (1322222231).

The spelling of 1101021220 in words is "one billion, one hundred one million, twenty-one thousand, two hundred twenty".