51968581 has 4 divisors (see below), whose sum is σ = 59392672. Its totient is φ = 44544492.

The previous prime is 51968561. The next prime is 51968593. The reversal of 51968581 is 18586915.

51968581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 51968581 - 2⁵ = 51968549 is a prime.

It is a super-2 number, since 2×51968581² = 5401466822307122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51968561) 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, 3712035 + ... + 3712048.

It is an arithmetic number, because the mean of its divisors is an integer number (14848168).

Almost surely, 2^51968581 is an apocalyptic number.

It is an amenable number.

51968581 is a deficient number, since it is larger than the sum of its proper divisors (7424091).

51968581 is an equidigital number, since it uses as much as digits as its factorization.

51968581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7424090.

The product of its digits is 86400, while the sum is 43.

The square root of 51968581 is about 7208.9237060743. The cubic root of 51968581 is about 373.1759263260.

The spelling of 51968581 in words is "fifty-one million, nine hundred sixty-eight thousand, five hundred eighty-one".