1011221020 has 12 divisors (see below), whose sum is σ = 2123564184. Its totient is φ = 404488400.

The previous prime is 1011221011. The next prime is 1011221033. The reversal of 1011221020 is 201221101.

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 = 1011220988 and 1011221006.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 25280506 + ... + 25280545.

It is an arithmetic number, because the mean of its divisors is an integer number (176963682).

Almost surely, 2^1011221020 is an apocalyptic number.

1011221020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1011221020 is an abundant number, since it is smaller than the sum of its proper divisors (1112343164).

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

1011221020 is a wasteful number, since it uses less digits than its factorization.

1011221020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50561060 (or 50561058 counting only the distinct ones).

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

The square root of 1011221020 is about 31799.7015709267. The cubic root of 1011221020 is about 1003.7264364227.

Adding to 1011221020 its reverse (201221101), we get a palindrome (1212442121).

The spelling of 1011221020 in words is "one billion, eleven million, two hundred twenty-one thousand, twenty".