51996640 has 24 divisors (see below), whose sum is σ = 122842440. Its totient is φ = 20798592.

The previous prime is 51996599. The next prime is 51996647. The reversal of 51996640 is 4669915.

51996640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 51996593 and 51996602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51996647) 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 3 ways as a sum of consecutive naturals, for example, 162330 + ... + 162649.

It is an arithmetic number, because the mean of its divisors is an integer number (5118435).

Almost surely, 2^51996640 is an apocalyptic number.

It is an amenable number.

51996640 is an abundant number, since it is smaller than the sum of its proper divisors (70845800).

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

51996640 is a wasteful number, since it uses less digits than its factorization.

51996640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324994 (or 324986 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 40.

The square root of 51996640 is about 7210.8695730820. The cubic root of 51996640 is about 373.2430762538.

The spelling of 51996640 in words is "fifty-one million, nine hundred ninety-six thousand, six hundred forty".