51030720 has 336 divisors, whose sum is σ = 199704960. Its totient is φ = 11870208.

The previous prime is 51030671. The next prime is 51030737. The reversal of 51030720 is 2703015.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 51030693 and 51030702.

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, 1085737 + ... + 1085783.

It is an arithmetic number, because the mean of its divisors is an integer number (594360).

Almost surely, 2^51030720 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 51030720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99852480).

51030720 is an abundant number, since it is smaller than the sum of its proper divisors (148674240).

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

51030720 is a wasteful number, since it uses less digits than its factorization.

51030720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112 (or 99 counting only the distinct ones).

The product of its (nonzero) digits is 210, while the sum is 18.

The square root of 51030720 is about 7143.5789349597. The cubic root of 51030720 is about 370.9174214340.

Adding to 51030720 its reverse (2703015), we get a palindrome (53733735).

The spelling of 51030720 in words is "fifty-one million, thirty thousand, seven hundred twenty".