51225020 has 192 divisors, whose sum is σ = 147087360. Its totient is φ = 14515200.

The previous prime is 51224963. The next prime is 51225023. The reversal of 51225020 is 2052215.

51225020 = 231² + 232² + ... + 549².

51225020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 51225020.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51225023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1384442 + ... + 1384478.

It is an arithmetic number, because the mean of its divisors is an integer number (766080).

Almost surely, 2^51225020 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 51225020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73543680).

51225020 is an abundant number, since it is smaller than the sum of its proper divisors (95862340).

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

51225020 is a wasteful number, since it uses less digits than its factorization.

51225020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 17.

The square root of 51225020 is about 7157.1656401120. The cubic root of 51225020 is about 371.3875825436.

Adding to 51225020 its reverse (2052215), we get a palindrome (53277235).

The spelling of 51225020 in words is "fifty-one million, two hundred twenty-five thousand, twenty".