55123321 has 16 divisors (see below), whose sum is σ = 61746048. Its totient is φ = 48787200.

The previous prime is 55123283. The next prime is 55123331. The reversal of 55123321 is 12332155.

It is not a de Polignac number, because 55123321 - 2¹¹ = 55121273 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 55123292 and 55123301.

It is not an unprimeable number, because it can be changed into a prime (55123331) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75460 + ... + 76186.

It is an arithmetic number, because the mean of its divisors is an integer number (3859128).

Almost surely, 2^55123321 is an apocalyptic number.

It is an amenable number.

55123321 is a deficient number, since it is larger than the sum of its proper divisors (6622727).

55123321 is a wasteful number, since it uses less digits than its factorization.

55123321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 912.

The product of its digits is 900, while the sum is 22.

The square root of 55123321 is about 7424.5081318563. The cubic root of 55123321 is about 380.5792665718.

Adding to 55123321 its reverse (12332155), we get a palindrome (67455476).

The spelling of 55123321 in words is "fifty-five million, one hundred twenty-three thousand, three hundred twenty-one".