51451520 has 64 divisors (see below), whose sum is σ = 130264200. Its totient is φ = 19365888.

The previous prime is 51451513. The next prime is 51451541. The reversal of 51451520 is 2515415.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 33269824 + 18181696 = 5768^2 + 4264^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8516 + ... + 13244.

Almost surely, 2^51451520 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 51451520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65132100).

51451520 is an abundant number, since it is smaller than the sum of its proper divisors (78812680).

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

51451520 is a wasteful number, since it uses less digits than its factorization.

51451520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4765 (or 4753 counting only the distinct ones).

The product of its (nonzero) digits is 1000, while the sum is 23.

The square root of 51451520 is about 7172.9714902542. The cubic root of 51451520 is about 371.9341618559.

Adding to 51451520 its reverse (2515415), we get a palindrome (53966935).

The spelling of 51451520 in words is "fifty-one million, four hundred fifty-one thousand, five hundred twenty".