51206400000 has 864 divisors, whose sum is σ = 212926371840. Its totient is φ = 11612160000.

The previous prime is 51206399989. The next prime is 51206400071. The reversal of 51206400000 is 460215.

It is a happy number.

51206400000 is a `hidden beast` number, since 5 + 1 + 20 + 640 + 0 + 0 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 403199937 + ... + 403200063.

It is an arithmetic number, because the mean of its divisors is an integer number (246442560).

Almost surely, 2^51206400000 is an apocalyptic number.

51206400000 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 51206400000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106463185920).

51206400000 is an abundant number, since it is smaller than the sum of its proper divisors (161719971840).

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

51206400000 is an equidigital number, since it uses as much as digits as its factorization.

51206400000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187 (or 144 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

Adding to 51206400000 its reverse (460215), we get a palindrome (51206860215).

It can be divided in two parts, 5120 and 6400000, that multiplied together give a cube (32768000000 = 3200³).

The spelling of 51206400000 in words is "fifty-one billion, two hundred six million, four hundred thousand".