51691300 has 54 divisors (see below), whose sum is σ = 114900198. Its totient is φ = 20183040.

The previous prime is 51691279. The next prime is 51691307. The reversal of 51691300 is 319615.

51691300 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 9 ways, for example, as 11546404 + 40144896 = 3398^2 + 6336^2 .

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

It is not an unprimeable number, because it can be changed into a prime (51691307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 532852 + ... + 532948.

Almost surely, 2^51691300 is an apocalyptic number.

51691300 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 51691300, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57450099).

51691300 is an abundant number, since it is smaller than the sum of its proper divisors (63208898).

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

51691300 is a wasteful number, since it uses less digits than its factorization.

51691300 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 810, while the sum is 25.

The square root of 51691300 is about 7189.6661953112. Note that the first 3 decimals coincide. The cubic root of 51691300 is about 372.5110427187.

The spelling of 51691300 in words is "fifty-one million, six hundred ninety-one thousand, three hundred".