51521040000 has 480 divisors, whose sum is σ = 186823322400. Its totient is φ = 13623552000.

The previous prime is 51521039963. The next prime is 51521040001. The reversal of 51521040000 is 4012515.

51521040000 is a `hidden beast` number, since 51 + 5 + 210 + 400 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (51521040001) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 117359781 + ... + 117360219.

It is an arithmetic number, because the mean of its divisors is an integer number (389215255).

Almost surely, 2^51521040000 is an apocalyptic number.

51521040000 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 51521040000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93411661200).

51521040000 is an abundant number, since it is smaller than the sum of its proper divisors (135302282400).

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

51521040000 is a wasteful number, since it uses less digits than its factorization.

51521040000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 642 (or 612 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

Adding to 51521040000 its reverse (4012515), we get a palindrome (51525052515).

The spelling of 51521040000 in words is "fifty-one billion, five hundred twenty-one million, forty thousand".