51540400000 has 192 divisors, whose sum is σ = 129085488000. Its totient is φ = 20496640000.

The previous prime is 51540399923. The next prime is 51540400061. The reversal of 51540400000 is 404515.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 107599761 + ... + 107600239.

It is an arithmetic number, because the mean of its divisors is an integer number (672320250).

Almost surely, 2^51540400000 is an apocalyptic number.

51540400000 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 51540400000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64542744000).

51540400000 is an abundant number, since it is smaller than the sum of its proper divisors (77545088000).

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

51540400000 is an frugal number, since it uses more digits than its factorization.

51540400000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 787 (or 755 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 19.

Adding to 51540400000 its reverse (404515), we get a palindrome (51540804515).

The spelling of 51540400000 in words is "fifty-one billion, five hundred forty million, four hundred thousand".