51110450820 has 720 divisors, whose sum is σ = 196218215424. Its totient is φ = 11051251200.

The previous prime is 51110450779. The next prime is 51110450843. The reversal of 51110450820 is 2805401115.

51110450820 is a `hidden beast` number, since 51 + 1 + 104 + 508 + 2 + 0 = 666.

It is a super-2 number, since 2×51110450820² (a number of 22 digits) contains 22 as substring.

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 (19) of ones.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 78995737 + ... + 78996383.

Almost surely, 2^51110450820 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 51110450820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98109107712).

51110450820 is an abundant number, since it is smaller than the sum of its proper divisors (145107764604).

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

51110450820 is a wasteful number, since it uses less digits than its factorization.

51110450820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 734 (or 712 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 27.

Adding to 51110450820 its reverse (2805401115), we get a palindrome (53915851935).

The spelling of 51110450820 in words is "fifty-one billion, one hundred ten million, four hundred fifty thousand, eight hundred twenty".