51939010981 has 16 divisors (see below), whose sum is σ = 61371999360. Its totient is φ = 43333225920.

The previous prime is 51939010927. The next prime is 51939011051. The reversal of 51939010981 is 18901093915.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51939010981 is a prime.

It is a super-2 number, since 2×51939010981² (a number of 22 digits) 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 (51939010381) 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 15 ways as a sum of consecutive naturals, for example, 1025001 + ... + 1074478.

It is an arithmetic number, because the mean of its divisors is an integer number (3835749960).

Almost surely, 2^51939010981 is an apocalyptic number.

It is an amenable number.

51939010981 is a deficient number, since it is larger than the sum of its proper divisors (9432988379).

51939010981 is a wasteful number, since it uses less digits than its factorization.

51939010981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2099676.

The product of its (nonzero) digits is 87480, while the sum is 46.

The spelling of 51939010981 in words is "fifty-one billion, nine hundred thirty-nine million, ten thousand, nine hundred eighty-one".