20010221021 has 16 divisors (see below), whose sum is σ = 22998245376. Its totient is φ = 17054829936.

The previous prime is 20010220987. The next prime is 20010221039. The reversal of 20010221021 is 12012201002.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20010221021 - 2³⁴ = 2830351837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20010220993 and 20010221011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20010221221) 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, 880220 + ... + 902666.

It is an arithmetic number, because the mean of its divisors is an integer number (1437390336).

Almost surely, 2^20010221021 is an apocalyptic number.

It is an amenable number.

20010221021 is a deficient number, since it is larger than the sum of its proper divisors (2988024355).

20010221021 is a wasteful number, since it uses less digits than its factorization.

20010221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23168.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 20010221021 its reverse (12012201002), we get a palindrome (32022422023).

The spelling of 20010221021 in words is "twenty billion, ten million, two hundred twenty-one thousand, twenty-one".