55123221 has 8 divisors (see below), whose sum is σ = 73674720. Its totient is φ = 36660272.

The previous prime is 55123219. The next prime is 55123223. The reversal of 55123221 is 12232155.

It is an interprime number because it is at equal distance from previous prime (55123219) and next prime (55123223).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 55123221 - 2¹ = 55123219 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55123223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20670 + ... + 23183.

It is an arithmetic number, because the mean of its divisors is an integer number (9209340).

Almost surely, 2^55123221 is an apocalyptic number.

It is an amenable number.

55123221 is a deficient number, since it is larger than the sum of its proper divisors (18551499).

55123221 is a wasteful number, since it uses less digits than its factorization.

55123221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44275.

The product of its digits is 600, while the sum is 21.

The square root of 55123221 is about 7424.5013974004. The cubic root of 55123221 is about 380.5790364336.

Adding to 55123221 its reverse (12232155), we get a palindrome (67355376).

The spelling of 55123221 in words is "fifty-five million, one hundred twenty-three thousand, two hundred twenty-one".