51644736 has 336 divisors, whose sum is σ = 189179200. Its totient is φ = 13685760.

The previous prime is 51644731. The next prime is 51644743. The reversal of 51644736 is 63744615.

It is a happy number.

51644736 is a `hidden beast` number, since 5 + 1 + 644 + 7 + 3 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

Its product of digits (60480) is a multiple of the sum of its prime divisors (48).

It is a self number, because there is not a number n which added to its sum of digits gives 51644736.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51644731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2718135 + ... + 2718153.

Almost surely, 2^51644736 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 51644736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94589600).

51644736 is an abundant number, since it is smaller than the sum of its proper divisors (137534464).

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

51644736 is a wasteful number, since it uses less digits than its factorization.

51644736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75 (or 48 counting only the distinct ones).

The product of its digits is 60480, while the sum is 36.

The square root of 51644736 is about 7186.4272068950. The cubic root of 51644736 is about 372.3991553208.

The spelling of 51644736 in words is "fifty-one million, six hundred forty-four thousand, seven hundred thirty-six".