20201100000021 has 24 divisors (see below), whose sum is σ = 29459841203520. Its totient is φ = 13338016626816.

The previous prime is 20201099999897. The next prime is 20201100000047. The reversal of 20201100000021 is 12000000110202.

It is not a de Polignac number, because 20201100000021 - 2¹⁴ = 20201099983637 is a prime.

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 = 20201099999949 and 20201100000012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20201100000421) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 887400 + ... + 6417918.

It is an arithmetic number, because the mean of its divisors is an integer number (1227493383480).

Almost surely, 2^{20201100000021} is an apocalyptic number.

It is an amenable number.

20201100000021 is a deficient number, since it is larger than the sum of its proper divisors (9258741203499).

20201100000021 is a wasteful number, since it uses less digits than its factorization.

20201100000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5534425 (or 5534422 counting only the distinct ones).

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

Adding to 20201100000021 its reverse (12000000110202), we get a palindrome (32201100110223).

The spelling of 20201100000021 in words is "twenty trillion, two hundred one billion, one hundred million, twenty-one", and thus it is an aban number.