51163840 has 168 divisors, whose sum is σ = 153235152. Its totient is φ = 16128000.

The previous prime is 51163787. The next prime is 51163841. The reversal of 51163840 is 4836115.

It is a super-3 number, since 3×51163840³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 51163799 and 51163808.

It is not an unprimeable number, because it can be changed into a prime (51163841) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 203715 + ... + 203965.

It is an arithmetic number, because the mean of its divisors is an integer number (912114).

Almost surely, 2^51163840 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 51163840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76617576).

51163840 is an abundant number, since it is smaller than the sum of its proper divisors (102071312).

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

51163840 is a wasteful number, since it uses less digits than its factorization.

51163840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 295 (or 278 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 51163840 is about 7152.8903248966. The cubic root of 51163840 is about 371.2396695119.

Adding to 51163840 its reverse (4836115), we get a palindrome (55999955).

It can be divided in two parts, 51163 and 840, that added together give a triangular number (52003 = T₃₂₂).

The spelling of 51163840 in words is "fifty-one million, one hundred sixty-three thousand, eight hundred forty".