10021021020 has 72 divisors (see below), whose sum is σ = 30408500304. Its totient is φ = 2671269888.

The previous prime is 10021021007. The next prime is 10021021039. The reversal of 10021021020 is 2012012001.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 10021020993 and 10021021011.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 555787 + ... + 573533.

It is an arithmetic number, because the mean of its divisors is an integer number (422340282).

Almost surely, 2^10021021020 is an apocalyptic number.

10021021020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

10021021020 is an abundant number, since it is smaller than the sum of its proper divisors (20387479284).

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

10021021020 is a wasteful number, since it uses less digits than its factorization.

10021021020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20899 (or 20894 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 10021021020 its reverse (2012012001), we get a palindrome (12033033021).

The spelling of 10021021020 in words is "ten billion, twenty-one million, twenty-one thousand, twenty".