51971800 has 48 divisors (see below), whose sum is σ = 123139440. Its totient is φ = 20392320.

The previous prime is 51971767. The next prime is 51971813. The reversal of 51971800 is 817915.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8149 + ... + 13051.

It is an arithmetic number, because the mean of its divisors is an integer number (2565405).

Almost surely, 2^51971800 is an apocalyptic number.

51971800 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 51971800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (61569720).

51971800 is an abundant number, since it is smaller than the sum of its proper divisors (71167640).

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

51971800 is a wasteful number, since it uses less digits than its factorization.

51971800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4972 (or 4963 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 31.

The square root of 51971800 is about 7209.1469675684. The cubic root of 51971800 is about 373.1836311641.

The spelling of 51971800 in words is "fifty-one million, nine hundred seventy-one thousand, eight hundred".