1000021020 has 48 divisors (see below), whose sum is σ = 2803157280. Its totient is φ = 266377216.

The previous prime is 1000021019. The next prime is 1000021027. The reversal of 1000021020 is 201200001.

It is a happy number.

1000021020 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

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 congruent number.

It is not an unprimeable number, because it can be changed into a prime (1000021027) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48436 + ... + 65924.

It is an arithmetic number, because the mean of its divisors is an integer number (58399110).

Almost surely, 2^1000021020 is an apocalyptic number.

1000021020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1000021020 is an abundant number, since it is smaller than the sum of its proper divisors (1803136260).

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

1000021020 is a wasteful number, since it uses less digits than its factorization.

1000021020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18454 (or 18452 counting only the distinct ones).

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

The square root of 1000021020 is about 31623.1089553194. The cubic root of 1000021020 is about 1000.0070066176.

Adding to 1000021020 its reverse (201200001), we get a palindrome (1201221021).

The spelling of 1000021020 in words is "one billion, twenty-one thousand, twenty".