1021002020 has 12 divisors (see below), whose sum is σ = 2144104284. Its totient is φ = 408400800.

The previous prime is 1021002001. The next prime is 1021002029. The reversal of 1021002020 is 202001201.

It can be written as a sum of positive squares in 2 ways, for example, as 275493604 + 745508416 = 16598^2 + 27304^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1021001989 and 1021002007.

It is not an unprimeable number, because it can be changed into a prime (1021002029) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25525031 + ... + 25525070.

It is an arithmetic number, because the mean of its divisors is an integer number (178675357).

Almost surely, 2^1021002020 is an apocalyptic number.

1021002020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021002020 is an abundant number, since it is smaller than the sum of its proper divisors (1123102264).

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

1021002020 is a wasteful number, since it uses less digits than its factorization.

1021002020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51050110 (or 51050108 counting only the distinct ones).

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

The square root of 1021002020 is about 31953.1222261612. The cubic root of 1021002020 is about 1006.9522278528.

Adding to 1021002020 its reverse (202001201), we get a palindrome (1223003221).

The spelling of 1021002020 in words is "one billion, twenty-one million, two thousand, twenty".