51855100 has 144 divisors (see below), whose sum is σ = 134991360. Its totient is φ = 17075200.

The previous prime is 51855091. The next prime is 51855101. The reversal of 51855100 is 155815.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51855101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 878871 + ... + 878929.

It is an arithmetic number, because the mean of its divisors is an integer number (937440).

Almost surely, 2^51855100 is an apocalyptic number.

51855100 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 51855100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67495680).

51855100 is an abundant number, since it is smaller than the sum of its proper divisors (83136260).

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

51855100 is a wasteful number, since it uses less digits than its factorization.

51855100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148 (or 141 counting only the distinct ones).

The product of its (nonzero) digits is 1000, while the sum is 25.

The square root of 51855100 is about 7201.0485347621. The cubic root of 51855100 is about 372.9041002947.

The spelling of 51855100 in words is "fifty-one million, eight hundred fifty-five thousand, one hundred".