55121443 has 4 divisors (see below), whose sum is σ = 59361568. Its totient is φ = 50881320.

The previous prime is 55121419. The next prime is 55121449. The reversal of 55121443 is 34412155.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34412155 = 5 ⋅6882431.

It is a cyclic number.

It is not a de Polignac number, because 55121443 - 2¹³ = 55113251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55121449) 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 in 3 ways as a sum of consecutive naturals, for example, 2120043 + ... + 2120068.

It is an arithmetic number, because the mean of its divisors is an integer number (14840392).

Almost surely, 2^55121443 is an apocalyptic number.

55121443 is a deficient number, since it is larger than the sum of its proper divisors (4240125).

55121443 is a wasteful number, since it uses less digits than its factorization.

55121443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4240124.

The product of its digits is 2400, while the sum is 25.

The square root of 55121443 is about 7424.3816577544. The cubic root of 55121443 is about 380.5749445295.

Adding to 55121443 its reverse (34412155), we get a palindrome (89533598).

The spelling of 55121443 in words is "fifty-five million, one hundred twenty-one thousand, four hundred forty-three".