51549894240 has 576 divisors, whose sum is σ = 192746433600. Its totient is φ = 11522015232.

The previous prime is 51549894139. The next prime is 51549894241. The reversal of 51549894240 is 4249894515.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51549894241) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 39991516 + ... + 39992804.

It is an arithmetic number, because the mean of its divisors is an integer number (334629225).

Almost surely, 2^51549894240 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 51549894240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96373216800).

51549894240 is an abundant number, since it is smaller than the sum of its proper divisors (141196539360).

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

51549894240 is a wasteful number, since it uses less digits than its factorization.

51549894240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1379 (or 1358 counting only the distinct ones).

The product of its (nonzero) digits is 2073600, while the sum is 51.

The spelling of 51549894240 in words is "fifty-one billion, five hundred forty-nine million, eight hundred ninety-four thousand, two hundred forty".