55123212420 has 192 divisors, whose sum is σ = 174888806400. Its totient is φ = 14410206720.

The previous prime is 55123212413. The next prime is 55123212451. The reversal of 55123212420 is 2421232155.

55123212420 is a `hidden beast` number, since 5 + 5 + 1 + 23 + 212 + 420 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 10439341 + ... + 10444619.

It is an arithmetic number, because the mean of its divisors is an integer number (910879200).

Almost surely, 2^55123212420 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 55123212420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87444403200).

55123212420 is an abundant number, since it is smaller than the sum of its proper divisors (119765593980).

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

55123212420 is a wasteful number, since it uses less digits than its factorization.

55123212420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5675 (or 5667 counting only the distinct ones).

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

Adding to 55123212420 its reverse (2421232155), we get a palindrome (57544444575).

The spelling of 55123212420 in words is "fifty-five billion, one hundred twenty-three million, two hundred twelve thousand, four hundred twenty".