2021400121 has 16 divisors (see below), whose sum is σ = 2223486720. Its totient is φ = 1826248320.

The previous prime is 2021400109. The next prime is 2021400131. The reversal of 2021400121 is 1210041202.

It is a happy number.

It is not a de Polignac number, because 2021400121 - 2⁵ = 2021400089 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is not an unprimeable number, because it can be changed into a prime (2021400131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 173056 + ... + 184366.

It is an arithmetic number, because the mean of its divisors is an integer number (138967920).

Almost surely, 2^2021400121 is an apocalyptic number.

It is an amenable number.

2021400121 is a deficient number, since it is larger than the sum of its proper divisors (202086599).

2021400121 is a wasteful number, since it uses less digits than its factorization.

2021400121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11616.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 2021400121 is about 44959.9835520433. The cubic root of 2021400121 is about 1264.3988605401.

Adding to 2021400121 its reverse (1210041202), we get a palindrome (3231441323).

The spelling of 2021400121 in words is "two billion, twenty-one million, four hundred thousand, one hundred twenty-one".