51002005520 has 80 divisors (see below), whose sum is σ = 125127408000. Its totient is φ = 19279586304.

The previous prime is 51002005469. The next prime is 51002005531. The reversal of 51002005520 is 2550020015.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×51002005520² (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 a junction number, because it is equal to n+sod(n) for n = 51002005492 and 51002005501.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 580661 + ... + 662699.

It is an arithmetic number, because the mean of its divisors is an integer number (1564092600).

Almost surely, 2^51002005520 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 51002005520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (62563704000).

51002005520 is an abundant number, since it is smaller than the sum of its proper divisors (74125402480).

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

51002005520 is a wasteful number, since it uses less digits than its factorization.

51002005520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82480 (or 82474 counting only the distinct ones).

The product of its (nonzero) digits is 500, while the sum is 20.

Adding to 51002005520 its reverse (2550020015), we get a palindrome (53552025535).

The spelling of 51002005520 in words is "fifty-one billion, two million, five thousand, five hundred twenty".