51817304726640 has 600 divisors, whose sum is σ = 190207275017760. Its totient is φ = 13072252013568.

The previous prime is 51817304726623. The next prime is 51817304726647. The reversal of 51817304726640 is 4662740371815.

51817304726640 is a `hidden beast` number, since 5 + 1 + 8 + 1 + 73 + 0 + 472 + 66 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51817304726647) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 1700641326 + ... + 1700671794.

Almost surely, 2^{51817304726640} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51817304726640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95103637508880).

51817304726640 is an abundant number, since it is smaller than the sum of its proper divisors (138389970291120).

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

51817304726640 is a wasteful number, since it uses less digits than its factorization.

51817304726640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31259 (or 31225 counting only the distinct ones).

The product of its (nonzero) digits is 6773760, while the sum is 54.

The spelling of 51817304726640 in words is "fifty-one trillion, eight hundred seventeen billion, three hundred four million, seven hundred twenty-six thousand, six hundred forty".