51311400 has 192 divisors, whose sum is σ = 191654400. Its totient is φ = 11093760.

The previous prime is 51311399. The next prime is 51311401. The reversal of 51311400 is 411315.

51311400 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (51311399) and next prime (51311401).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 51311400.

It is not an unprimeable number, because it can be changed into a prime (51311401) 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 47 ways as a sum of consecutive naturals, for example, 79479 + ... + 80121.

It is an arithmetic number, because the mean of its divisors is an integer number (998200).

Almost surely, 2^51311400 is an apocalyptic number.

51311400 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 51311400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95827200).

51311400 is an abundant number, since it is smaller than the sum of its proper divisors (140343000).

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

51311400 is a wasteful number, since it uses less digits than its factorization.

51311400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 688 (or 679 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 15.

The square root of 51311400 is about 7163.1976100063. The cubic root of 51311400 is about 371.5962204578.

Adding to 51311400 its reverse (411315), we get a palindrome (51722715).

The spelling of 51311400 in words is "fifty-one million, three hundred eleven thousand, four hundred".