2121201021 has 16 divisors (see below), whose sum is σ = 2998553600. Its totient is φ = 1330062768.

The previous prime is 2121200987. The next prime is 2121201029. The reversal of 2121201021 is 1201021212.

It is not a de Polignac number, because 2121201021 - 2⁶ = 2121200957 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2121200988 and 2121201006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121201029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 125941 + ... + 141786.

It is an arithmetic number, because the mean of its divisors is an integer number (187409600).

Almost surely, 2^2121201021 is an apocalyptic number.

It is an amenable number.

2121201021 is a deficient number, since it is larger than the sum of its proper divisors (877352579).

2121201021 is a wasteful number, since it uses less digits than its factorization.

2121201021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267888.

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

The square root of 2121201021 is about 46056.4981408704. The cubic root of 2121201021 is about 1284.8742014758.

Adding to 2121201021 its reverse (1201021212), we get a palindrome (3322222233).

It can be divided in two parts, 212 and 1201021, that multiplied together give a palindrome (254616452).

The spelling of 2121201021 in words is "two billion, one hundred twenty-one million, two hundred one thousand, twenty-one".