51684369408 has 704 divisors, whose sum is σ = 193556459520. Its totient is φ = 13274578944.

The previous prime is 51684369403. The next prime is 51684369409. The reversal of 51684369408 is 80496348615.

51684369408 is a `hidden beast` number, since 5 + 168 + 436 + 9 + 40 + 8 = 666.

It is a super-2 number, since 2×51684369408² (a number of 22 digits) contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (51684369403) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 75672235 + ... + 75672917.

Almost surely, 2^51684369408 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 51684369408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96778229760).

51684369408 is an abundant number, since it is smaller than the sum of its proper divisors (141872090112).

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

51684369408 is a wasteful number, since it uses less digits than its factorization.

51684369408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 759 (or 735 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 54.

The spelling of 51684369408 in words is "fifty-one billion, six hundred eighty-four million, three hundred sixty-nine thousand, four hundred eight".