2120200000021 has 4 divisors (see below), whose sum is σ = 2126973802252. Its totient is φ = 2113426197792.

The previous prime is 2120199999971. The next prime is 2120200000049. The reversal of 2120200000021 is 1200000020212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1031748062500 + 1088451937521 = 1015750^2 + 1043289^2 .

It is a cyclic number.

It is not a de Polignac number, because 2120200000021 - 2¹¹ = 2120199997973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2120199999953 and 2120200000007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2120200000081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3386900646 + ... + 3386901271.

It is an arithmetic number, because the mean of its divisors is an integer number (531743450563).

Almost surely, 2^{2120200000021} is an apocalyptic number.

It is an amenable number.

2120200000021 is a deficient number, since it is larger than the sum of its proper divisors (6773802231).

2120200000021 is an equidigital number, since it uses as much as digits as its factorization.

2120200000021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6773802230.

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 2120200000021 its reverse (1200000020212), we get a palindrome (3320200020233).

The spelling of 2120200000021 in words is "two trillion, one hundred twenty billion, two hundred million, twenty-one", and thus it is an aban number.