51751644 has 72 divisors (see below), whose sum is σ = 141418368. Its totient is φ = 14686560.

The previous prime is 51751643. The next prime is 51751669. The reversal of 51751644 is 44615715.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51751643) 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, 166249 + ... + 166559.

It is an arithmetic number, because the mean of its divisors is an integer number (1964144).

Almost surely, 2^51751644 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 51751644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70709184).

51751644 is an abundant number, since it is smaller than the sum of its proper divisors (89666724).

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

51751644 is a wasteful number, since it uses less digits than its factorization.

51751644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 615 (or 606 counting only the distinct ones).

The product of its digits is 16800, while the sum is 33.

The square root of 51751644 is about 7193.8615499605. The cubic root of 51751644 is about 372.6559417949.

The spelling of 51751644 in words is "fifty-one million, seven hundred fifty-one thousand, six hundred forty-four".