51123213200 has 120 divisors (see below), whose sum is σ = 128332708800. Its totient is φ = 19534394880.

The previous prime is 51123213191. The next prime is 51123213259. The reversal of 51123213200 is 231232115.

It is a super-2 number, since 2×51123213200² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7899566 + ... + 7906034.

It is an arithmetic number, because the mean of its divisors is an integer number (1069439240).

Almost surely, 2^51123213200 is an apocalyptic number.

51123213200 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51123213200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64166354400).

51123213200 is an abundant number, since it is smaller than the sum of its proper divisors (77209495600).

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

51123213200 is a wasteful number, since it uses less digits than its factorization.

51123213200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7369 (or 7358 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 20.

Adding to 51123213200 its reverse (231232115), we get a palindrome (51354445315).

The spelling of 51123213200 in words is "fifty-one billion, one hundred twenty-three million, two hundred thirteen thousand, two hundred".