2154040121 has 2 divisors, whose sum is σ = 2154040122. Its totient is φ = 2154040120.

The previous prime is 2154040087. The next prime is 2154040123. The reversal of 2154040121 is 1210404512.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1809566521 + 344473600 = 42539^2 + 18560^2 .

It is a cyclic number.

It is not a de Polignac number, because 2154040121 - 2²⁶ = 2086931257 is a prime.

Together with 2154040123, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 2154040093 and 2154040102.

It is not a weakly prime, because it can be changed into another prime (2154040123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1077020060 + 1077020061.

It is an arithmetic number, because the mean of its divisors is an integer number (1077020061).

Almost surely, 2^2154040121 is an apocalyptic number.

It is an amenable number.

2154040121 is a deficient number, since it is larger than the sum of its proper divisors (1).

2154040121 is an equidigital number, since it uses as much as digits as its factorization.

2154040121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 2154040121 is about 46411.6377754546. The cubic root of 2154040121 is about 1291.4708142276.

Adding to 2154040121 its reverse (1210404512), we get a palindrome (3364444633).

The spelling of 2154040121 in words is "two billion, one hundred fifty-four million, forty thousand, one hundred twenty-one".