51286320 has 240 divisors, whose sum is σ = 190344960. Its totient is φ = 12317184.

The previous prime is 51286271. The next prime is 51286321. The reversal of 51286320 is 2368215.

51286320 is a `hidden beast` number, since 5 + 1 + 28 + 632 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is not an unprimeable number, because it can be changed into a prime (51286321) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 314559 + ... + 314721.

It is an arithmetic number, because the mean of its divisors is an integer number (793104).

Almost surely, 2^51286320 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 51286320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95172480).

51286320 is an abundant number, since it is smaller than the sum of its proper divisors (139058640).

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

51286320 is a wasteful number, since it uses less digits than its factorization.

51286320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224 (or 215 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 51286320 is about 7161.4467812028. The cubic root of 51286320 is about 371.5356676240.

The spelling of 51286320 in words is "fifty-one million, two hundred eighty-six thousand, three hundred twenty".