20101020000021 has 10 divisors (see below), whose sum is σ = 30027449629782. Its totient is φ = 13400679999960.

The previous prime is 20101020000001. The next prime is 20101020000029. The reversal of 20101020000021 is 12000002010102.

It can be written as a sum of positive squares in only one way, i.e., 19619460336996 + 481559663025 = 4429386^2 + 693945^2 .

It is not a de Polignac number, because 20101020000021 - 2¹⁴ = 20101019983637 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 = 20101019999958 and 20101020000012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20101020000029) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 124080370290 + ... + 124080370451.

Almost surely, 2^{20101020000021} is an apocalyptic number.

It is an amenable number.

20101020000021 is a deficient number, since it is larger than the sum of its proper divisors (9926429629761).

20101020000021 is an equidigital number, since it uses as much as digits as its factorization.

20101020000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248160740753 (or 248160740744 counting only the distinct ones).

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

Adding to 20101020000021 its reverse (12000002010102), we get a palindrome (32101022010123).

The spelling of 20101020000021 in words is "twenty trillion, one hundred one billion, twenty million, twenty-one", and thus it is an aban number.