1021220020 has 24 divisors (see below), whose sum is σ = 2149555968. Its totient is φ = 407536800.

The previous prime is 1021219957. The next prime is 1021220021. The reversal of 1021220020 is 200221201.

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 = 1021219979 and 1021220006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021220021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50616 + ... + 67855.

It is an arithmetic number, because the mean of its divisors is an integer number (89564832).

Almost surely, 2^1021220020 is an apocalyptic number.

1021220020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021220020 is an abundant number, since it is smaller than the sum of its proper divisors (1128335948).

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

1021220020 is a wasteful number, since it uses less digits than its factorization.

1021220020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118911 (or 118909 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 1021220020 is about 31956.5332913318. The cubic root of 1021220020 is about 1007.0238894688.

Adding to 1021220020 its reverse (200221201), we get a palindrome (1221441221).

The spelling of 1021220020 in words is "one billion, twenty-one million, two hundred twenty thousand, twenty".