51247728 has 180 divisors, whose sum is σ = 173660760. Its totient is φ = 14587776.

The previous prime is 51247717. The next prime is 51247733. The reversal of 51247728 is 82774215.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 51247692 and 51247701.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 190378 + ... + 190646.

It is an arithmetic number, because the mean of its divisors is an integer number (964782).

Almost surely, 2^51247728 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 51247728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86830380).

51247728 is an abundant number, since it is smaller than the sum of its proper divisors (122413032).

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

51247728 is a wasteful number, since it uses less digits than its factorization.

51247728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306 (or 281 counting only the distinct ones).

The product of its digits is 31360, while the sum is 36.

The square root of 51247728 is about 7158.7518465163. The cubic root of 51247728 is about 371.4424530174.

The spelling of 51247728 in words is "fifty-one million, two hundred forty-seven thousand, seven hundred twenty-eight".