51816399206400 has 864 divisors, whose sum is σ = 196164757152000. Its totient is φ = 13035160535040.

The previous prime is 51816399206399. The next prime is 51816399206401. The reversal of 51816399206400 is 460299361815.

51816399206400 is a `hidden beast` number, since 5 + 1 + 8 + 1 + 6 + 399 + 206 + 40 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (51816399206399) and next prime (51816399206401).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51816399206401) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2092480419 + ... + 2092505181.

It is an arithmetic number, because the mean of its divisors is an integer number (227042543000).

Almost surely, 2^{51816399206400} is an apocalyptic number.

51816399206400 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 51816399206400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98082378576000).

51816399206400 is an abundant number, since it is smaller than the sum of its proper divisors (144348357945600).

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

51816399206400 is a wasteful number, since it uses less digits than its factorization.

51816399206400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25059 (or 25031 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 54.

The spelling of 51816399206400 in words is "fifty-one trillion, eight hundred sixteen billion, three hundred ninety-nine million, two hundred six thousand, four hundred".