51005545500 has 288 divisors, whose sum is σ = 186071715648. Its totient is φ = 10761408000.

The previous prime is 51005545471. The next prime is 51005545537. The reversal of 51005545500 is 554550015.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

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 95 ways as a sum of consecutive naturals, for example, 928810 + ... + 982190.

It is an arithmetic number, because the mean of its divisors is an integer number (646082346).

Almost surely, 2^51005545500 is an apocalyptic number.

51005545500 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 51005545500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93035857824).

51005545500 is an abundant number, since it is smaller than the sum of its proper divisors (135066170148).

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

51005545500 is a wasteful number, since it uses less digits than its factorization.

51005545500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53430 (or 53411 counting only the distinct ones).

The product of its (nonzero) digits is 12500, while the sum is 30.

It can be divided in two parts, 510055 and 45500, that added together give a palindrome (555555).

The spelling of 51005545500 in words is "fifty-one billion, five million, five hundred forty-five thousand, five hundred".