51943731840 has 2160 divisors, whose sum is σ = 256835106990. Its totient is φ = 9963233280.

The previous prime is 51943731839. The next prime is 51943731841. The reversal of 51943731840 is 4813734915.

It is an interprime number because it is at equal distance from previous prime (51943731839) and next prime (51943731841).

It can be written as a sum of positive squares in 3 ways, for example, as 22406497344 + 29537234496 = 149688^2 + 171864^2 .

It is a tau number, because it is divible by the number of its divisors (2160).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (51943731841) by changing a digit.

It is a polite number, since it can be written in 269 ways as a sum of consecutive naturals, for example, 3995671674 + ... + 3995671686.

Almost surely, 2^51943731840 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 51943731840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (128417553495).

51943731840 is an abundant number, since it is smaller than the sum of its proper divisors (204891375150).

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

51943731840 is a wasteful number, since it uses less digits than its factorization.

51943731840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The spelling of 51943731840 in words is "fifty-one billion, nine hundred forty-three million, seven hundred thirty-one thousand, eight hundred forty".