1020021000 has 64 divisors (see below), whose sum is σ = 3182474880. Its totient is φ = 272004800.

The previous prime is 1020020983. The next prime is 1020021127. The reversal of 1020021000 is 1200201.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a self number, because there is not a number n which added to its sum of digits gives 1020021000.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 167004 + ... + 173003.

It is an arithmetic number, because the mean of its divisors is an integer number (49726170).

Almost surely, 2^1020021000 is an apocalyptic number.

1020021000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1020021000 is an abundant number, since it is smaller than the sum of its proper divisors (2162453880).

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

1020021000 is a wasteful number, since it uses less digits than its factorization.

1020021000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340031 (or 340017 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 6.

The square root of 1020021000 is about 31937.7676114033. The cubic root of 1020021000 is about 1006.6296177078.

Adding to 1020021000 its reverse (1200201), we get a palindrome (1021221201).

The spelling of 1020021000 in words is "one billion, twenty million, twenty-one thousand".