51720566 has 8 divisors (see below), whose sum is σ = 77920320. Its totient is φ = 25747128.

The previous prime is 51720563. The next prime is 51720593. The reversal of 51720566 is 66502715.

It is a happy number.

51720566 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51720563) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 56006 + ... + 56921.

It is an arithmetic number, because the mean of its divisors is an integer number (9740040).

Almost surely, 2^51720566 is an apocalyptic number.

51720566 is a deficient number, since it is larger than the sum of its proper divisors (26199754).

51720566 is a wasteful number, since it uses less digits than its factorization.

51720566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113158.

The product of its (nonzero) digits is 12600, while the sum is 32.

The square root of 51720566 is about 7191.7011895657. The cubic root of 51720566 is about 372.5813308290.

The spelling of 51720566 in words is "fifty-one million, seven hundred twenty thousand, five hundred sixty-six".