51439327681 has 8 divisors (see below), whose sum is σ = 60684184064. Its totient is φ = 42668566560.

The previous prime is 51439327673. The next prime is 51439327691. The reversal of 51439327681 is 18672393415.

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

It is a cyclic number.

It is not a de Polignac number, because 51439327681 - 2³ = 51439327673 is a prime.

It is a super-2 number, since 2×51439327681² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (51439327691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 118523580 + ... + 118524013.

It is an arithmetic number, because the mean of its divisors is an integer number (7585523008).

Almost surely, 2^51439327681 is an apocalyptic number.

It is an amenable number.

51439327681 is a deficient number, since it is larger than the sum of its proper divisors (9244856383).

51439327681 is a wasteful number, since it uses less digits than its factorization.

51439327681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 237047631.

The product of its digits is 1088640, while the sum is 49.

The spelling of 51439327681 in words is "fifty-one billion, four hundred thirty-nine million, three hundred twenty-seven thousand, six hundred eighty-one".