55121221541 has 2 divisors, whose sum is σ = 55121221542. Its totient is φ = 55121221540.

The previous prime is 55121221471. The next prime is 55121221559. The reversal of 55121221541 is 14512212155.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27912719041 + 27208502500 = 167071^2 + 164950^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55121221541 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55121220541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27560610770 + 27560610771.

It is an arithmetic number, because the mean of its divisors is an integer number (27560610771).

Almost surely, 2^55121221541 is an apocalyptic number.

It is an amenable number.

55121221541 is a deficient number, since it is larger than the sum of its proper divisors (1).

55121221541 is an equidigital number, since it uses as much as digits as its factorization.

55121221541 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4000, while the sum is 29.

Adding to 55121221541 its reverse (14512212155), we get a palindrome (69633433696).

The spelling of 55121221541 in words is "fifty-five billion, one hundred twenty-one million, two hundred twenty-one thousand, five hundred forty-one".