51720528 has 80 divisors (see below), whose sum is σ = 142598016. Its totient is φ = 16097280.

The previous prime is 51720517. The next prime is 51720563. The reversal of 51720528 is 82502715.

It is a junction number, because it is equal to n+sod(n) for n = 51720495 and 51720504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 196525 + ... + 196787.

Almost surely, 2^51720528 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 51720528, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71299008).

51720528 is an abundant number, since it is smaller than the sum of its proper divisors (90877488).

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

51720528 is a wasteful number, since it uses less digits than its factorization.

51720528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 532 (or 526 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 30.

The square root of 51720528 is about 7191.6985476312. The cubic root of 51720528 is about 372.5812395817.

The spelling of 51720528 in words is "fifty-one million, seven hundred twenty thousand, five hundred twenty-eight".