51521002400 has 288 divisors, whose sum is σ = 152837217792. Its totient is φ = 16555622400.

The previous prime is 51521002399. The next prime is 51521002469. The reversal of 51521002400 is 420012515.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 25798202 + ... + 25800198.

It is an arithmetic number, because the mean of its divisors is an integer number (530684784).

Almost surely, 2^51521002400 is an apocalyptic number.

51521002400 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 51521002400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76418608896).

51521002400 is an abundant number, since it is smaller than the sum of its proper divisors (101316215392).

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

51521002400 is a wasteful number, since it uses less digits than its factorization.

51521002400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2312 (or 2299 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 20.

Adding to 51521002400 its reverse (420012515), we get a palindrome (51941014915).

The spelling of 51521002400 in words is "fifty-one billion, five hundred twenty-one million, two thousand, four hundred".