51491181952 has 256 divisors, whose sum is σ = 133367040000. Its totient is φ = 19670999040.

The previous prime is 51491181947. The next prime is 51491181991. The reversal of 51491181952 is 25918119415.

51491181952 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14179177 + ... + 14182807.

It is an arithmetic number, because the mean of its divisors is an integer number (520965000).

Almost surely, 2^51491181952 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51491181952, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66683520000).

51491181952 is an abundant number, since it is smaller than the sum of its proper divisors (81875858048).

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

51491181952 is a wasteful number, since it uses less digits than its factorization.

51491181952 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3702 (or 3676 counting only the distinct ones).

The product of its digits is 129600, while the sum is 46.

The spelling of 51491181952 in words is "fifty-one billion, four hundred ninety-one million, one hundred eighty-one thousand, nine hundred fifty-two".