55543421 has 4 divisors (see below), whose sum is σ = 55598844. Its totient is φ = 55488000.

The previous prime is 55543343. The next prime is 55543451. The reversal of 55543421 is 12434555.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 36060025 + 19483396 = 6005^2 + 4414^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55543421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55543451) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26180 + ... + 28221.

It is an arithmetic number, because the mean of its divisors is an integer number (13899711).

Almost surely, 2^55543421 is an apocalyptic number.

It is an amenable number.

55543421 is a deficient number, since it is larger than the sum of its proper divisors (55423).

55543421 is a wasteful number, since it uses less digits than its factorization.

55543421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55422.

The product of its digits is 12000, while the sum is 29.

The square root of 55543421 is about 7452.7458698120. The cubic root of 55543421 is about 381.5436309644.

Adding to 55543421 its reverse (12434555), we get a palindrome (67977976).

The spelling of 55543421 in words is "fifty-five million, five hundred forty-three thousand, four hundred twenty-one".