51706656 has 144 divisors (see below), whose sum is σ = 159213600. Its totient is φ = 15857664.

The previous prime is 51706651. The next prime is 51706663. The reversal of 51706656 is 65660715.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (144).

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

It is a self number, because there is not a number n which added to its sum of digits gives 51706656.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51706651) 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, 288775 + ... + 288953.

It is an arithmetic number, because the mean of its divisors is an integer number (1105650).

Almost surely, 2^51706656 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 51706656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79606800).

51706656 is an abundant number, since it is smaller than the sum of its proper divisors (107506944).

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

51706656 is a wasteful number, since it uses less digits than its factorization.

51706656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271 (or 260 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 36.

The square root of 51706656 is about 7190.7340376348. The cubic root of 51706656 is about 372.5479265091.

The spelling of 51706656 in words is "fifty-one million, seven hundred six thousand, six hundred fifty-six".