51021232320 has 224 divisors, whose sum is σ = 172143042048. Its totient is φ = 12758925312.

The previous prime is 51021232313. The next prime is 51021232351. The reversal of 51021232320 is 2323212015.

It is a super-2 number, since 2×51021232320² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4613037 + ... + 4624083.

Almost surely, 2^51021232320 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 51021232320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86071521024).

51021232320 is an abundant number, since it is smaller than the sum of its proper divisors (121121809728).

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

51021232320 is a wasteful number, since it uses less digits than its factorization.

51021232320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11367 (or 11357 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 21.

Adding to 51021232320 its reverse (2323212015), we get a palindrome (53344444335).

The spelling of 51021232320 in words is "fifty-one billion, twenty-one million, two hundred thirty-two thousand, three hundred twenty".