55123221420 has 144 divisors (see below), whose sum is σ = 176114615040. Its totient is φ = 13917391488.

The previous prime is 55123221407. The next prime is 55123221427. The reversal of 55123221420 is 2412232155.

55123221420 is a `hidden beast` number, since 5 + 5 + 1 + 232 + 2 + 1 + 420 = 666.

It is not an unprimeable number, because it can be changed into a prime (55123221427) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7133679 + ... + 7141401.

It is an arithmetic number, because the mean of its divisors is an integer number (1223018160).

Almost surely, 2^55123221420 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55123221420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88057307520).

55123221420 is an abundant number, since it is smaller than the sum of its proper divisors (120991393620).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

55123221420 is a wasteful number, since it uses less digits than its factorization.

55123221420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9844 (or 9839 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

Adding to 55123221420 its reverse (2412232155), we get a palindrome (57535453575).

The spelling of 55123221420 in words is "fifty-five billion, one hundred twenty-three million, two hundred twenty-one thousand, four hundred twenty".