51881946320 has 20 divisors (see below), whose sum is σ = 120625525380. Its totient is φ = 20752778496.

The previous prime is 51881946317. The next prime is 51881946323. The reversal of 51881946320 is 2364918815.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (51881946317) and next prime (51881946323).

It can be written as a sum of positive squares in 2 ways, for example, as 10893514384 + 40988431936 = 104372^2 + 202456^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51881946323) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 324262085 + ... + 324262244.

It is an arithmetic number, because the mean of its divisors is an integer number (6031276269).

Almost surely, 2^51881946320 is an apocalyptic number.

It is an amenable number.

51881946320 is an abundant number, since it is smaller than the sum of its proper divisors (68743579060).

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

51881946320 is a wasteful number, since it uses less digits than its factorization.

51881946320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 648524342 (or 648524336 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 47.

The spelling of 51881946320 in words is "fifty-one billion, eight hundred eighty-one million, nine hundred forty-six thousand, three hundred twenty".