51865500 has 96 divisors (see below), whose sum is σ = 153474048. Its totient is φ = 13608000.

The previous prime is 51865481. The next prime is 51865507. The reversal of 51865500 is 556815.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51865507) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 106257 + ... + 106743.

It is an arithmetic number, because the mean of its divisors is an integer number (1598688).

Almost surely, 2^51865500 is an apocalyptic number.

51865500 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51865500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76737024).

51865500 is an abundant number, since it is smaller than the sum of its proper divisors (101608548).

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

51865500 is a wasteful number, since it uses less digits than its factorization.

51865500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 580 (or 568 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 30.

The square root of 51865500 is about 7201.7706156195. The cubic root of 51865500 is about 372.9290283693.

The spelling of 51865500 in words is "fifty-one million, eight hundred sixty-five thousand, five hundred".