51302720 has 112 divisors (see below), whose sum is σ = 143621760. Its totient is φ = 17086464.

The previous prime is 51302707. The next prime is 51302723. The reversal of 51302720 is 2720315.

It is a tau number, because it is divible by the number of its divisors (112).

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 = 51302692 and 51302701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51302723) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 82571 + ... + 83189.

Almost surely, 2^51302720 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 51302720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71810880).

51302720 is an abundant number, since it is smaller than the sum of its proper divisors (92319040).

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

51302720 is a wasteful number, since it uses less digits than its factorization.

51302720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 680 (or 670 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 20.

The square root of 51302720 is about 7162.5917097096. The cubic root of 51302720 is about 371.5752658091.

The spelling of 51302720 in words is "fifty-one million, three hundred two thousand, seven hundred twenty".