51163640 has 96 divisors (see below), whose sum is σ = 130837680. Its totient is φ = 18004800.

The previous prime is 51163573. The next prime is 51163643. The reversal of 51163640 is 4636115.

51163640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51163643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1650425 + ... + 1650455.

Almost surely, 2^51163640 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 51163640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65418840).

51163640 is an abundant number, since it is smaller than the sum of its proper divisors (79674040).

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

51163640 is a wasteful number, since it uses less digits than its factorization.

51163640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106 (or 49 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 51163640 is about 7152.8763445204. The cubic root of 51163640 is about 371.2391857847.

Adding to 51163640 its reverse (4636115), we get a palindrome (55799755).

The spelling of 51163640 in words is "fifty-one million, one hundred sixty-three thousand, six hundred forty".