51285920 has 96 divisors (see below), whose sum is σ = 143337600. Its totient is φ = 16966656.

The previous prime is 51285919. The next prime is 51285943. The reversal of 51285920 is 2958215.

It is a Harshad number since it is a multiple of its sum of digits (32).

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, 31691 + ... + 33269.

It is an arithmetic number, because the mean of its divisors is an integer number (1493100).

Almost surely, 2^51285920 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 51285920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71668800).

51285920 is an abundant number, since it is smaller than the sum of its proper divisors (92051680).

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

51285920 is a wasteful number, since it uses less digits than its factorization.

51285920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1630 (or 1622 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 32.

The square root of 51285920 is about 7161.4188538306. The cubic root of 51285920 is about 371.5347017091.

The spelling of 51285920 in words is "fifty-one million, two hundred eighty-five thousand, nine hundred twenty".