2154432121 has 2 divisors, whose sum is σ = 2154432122. Its totient is φ = 2154432120.

The previous prime is 2154432113. The next prime is 2154432187. The reversal of 2154432121 is 1212344512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1327582096 + 826850025 = 36436^2 + 28755^2 .

It is a cyclic number.

It is not a de Polignac number, because 2154432121 - 2³ = 2154432113 is a prime.

It is not a weakly prime, because it can be changed into another prime (2154432421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1077216060 + 1077216061.

It is an arithmetic number, because the mean of its divisors is an integer number (1077216061).

Almost surely, 2^2154432121 is an apocalyptic number.

It is an amenable number.

2154432121 is a deficient number, since it is larger than the sum of its proper divisors (1).

2154432121 is an equidigital number, since it uses as much as digits as its factorization.

2154432121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1920, while the sum is 25.

The square root of 2154432121 is about 46415.8606620625. The cubic root of 2154432121 is about 1291.5491516500.

Adding to 2154432121 its reverse (1212344512), we get a palindrome (3366776633).

The spelling of 2154432121 in words is "two billion, one hundred fifty-four million, four hundred thirty-two thousand, one hundred twenty-one".