2021100120021 has 16 divisors (see below), whose sum is σ = 2723428813248. Its totient is φ = 1333146796800.

The previous prime is 2021100120007. The next prime is 2021100120029. The reversal of 2021100120021 is 1200210011202.

It is not a de Polignac number, because 2021100120021 - 2⁵ = 2021100119989 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2021100119979 and 2021100120006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021100120029) 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, 7497750 + ... + 7762631.

It is an arithmetic number, because the mean of its divisors is an integer number (170214300828).

Almost surely, 2^{2021100120021} is an apocalyptic number.

It is an amenable number.

2021100120021 is a deficient number, since it is larger than the sum of its proper divisors (702328693227).

2021100120021 is a wasteful number, since it uses less digits than its factorization.

2021100120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15260852.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 2021100120021 its reverse (1200210011202), we get a palindrome (3221310131223).

The spelling of 2021100120021 in words is "two trillion, twenty-one billion, one hundred million, one hundred twenty thousand, twenty-one".