51211323504 has 480 divisors, whose sum is σ = 169290950400. Its totient is φ = 14287933440.

The previous prime is 51211323491. The next prime is 51211323539. The reversal of 51211323504 is 40532311215.

51211323504 is a `hidden beast` number, since 5 + 1 + 21 + 132 + 3 + 504 = 666.

It is a congruent number.

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 95 ways as a sum of consecutive naturals, for example, 219790972 + ... + 219791204.

It is an arithmetic number, because the mean of its divisors is an integer number (352689480).

Almost surely, 2^51211323504 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 51211323504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84645475200).

51211323504 is an abundant number, since it is smaller than the sum of its proper divisors (118079626896).

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

51211323504 is a wasteful number, since it uses less digits than its factorization.

51211323504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 453 (or 444 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

Adding to 51211323504 its reverse (40532311215), we get a palindrome (91743634719).

The spelling of 51211323504 in words is "fifty-one billion, two hundred eleven million, three hundred twenty-three thousand, five hundred four".