51868440 has 96 divisors (see below), whose sum is σ = 181555920. Its totient is φ = 12766464.

The previous prime is 51868433. The next prime is 51868457. The reversal of 51868440 is 4486815.

51868440 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 (36).

It is a junction number, because it is equal to n+sod(n) for n = 51868395 and 51868404.

It is a congruent number.

It is an unprimeable number.

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, 862 + ... + 10221.

Almost surely, 2^51868440 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 51868440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90777960).

51868440 is an abundant number, since it is smaller than the sum of its proper divisors (129687480).

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

51868440 is a wasteful number, since it uses less digits than its factorization.

51868440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11113 (or 11106 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 51868440 is about 7201.9747291975. The cubic root of 51868440 is about 372.9360747401.

The spelling of 51868440 in words is "fifty-one million, eight hundred sixty-eight thousand, four hundred forty".