51747840 has 132 divisors (see below), whose sum is σ = 179464584. Its totient is φ = 13787136.

The previous prime is 51747827. The next prime is 51747869. The reversal of 51747840 is 4874715.

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 = 51747795 and 51747804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45519 + ... + 46641.

Almost surely, 2^51747840 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 51747840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89732292).

51747840 is an abundant number, since it is smaller than the sum of its proper divisors (127716744).

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

51747840 is a wasteful number, since it uses less digits than its factorization.

51747840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1154 (or 1133 counting only the distinct ones).

The product of its (nonzero) digits is 31360, while the sum is 36.

The square root of 51747840 is about 7193.5971530243. The cubic root of 51747840 is about 372.6468108905.

The spelling of 51747840 in words is "fifty-one million, seven hundred forty-seven thousand, eight hundred forty".