51909698400 has 864 divisors, whose sum is σ = 210316538880. Its totient is φ = 11063808000.

The previous prime is 51909698389. The next prime is 51909698411. The reversal of 51909698400 is 489690915.

It is an interprime number because it is at equal distance from previous prime (51909698389) and next prime (51909698411).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 105722155 + ... + 105722645.

It is an arithmetic number, because the mean of its divisors is an integer number (243421920).

Almost surely, 2^51909698400 is an apocalyptic number.

51909698400 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 51909698400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105158269440).

51909698400 is an abundant number, since it is smaller than the sum of its proper divisors (158406840480).

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

51909698400 is a wasteful number, since it uses less digits than its factorization.

51909698400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 588 (or 568 counting only the distinct ones).

The product of its (nonzero) digits is 699840, while the sum is 51.

The spelling of 51909698400 in words is "fifty-one billion, nine hundred nine million, six hundred ninety-eight thousand, four hundred".