51565436240 has 80 divisors (see below), whose sum is σ = 120414406080. Its totient is φ = 20536104960.

The previous prime is 51565436207. The next prime is 51565436249. The reversal of 51565436240 is 4263456515.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51565436249) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23860760 + ... + 23862920.

It is an arithmetic number, because the mean of its divisors is an integer number (1505180076).

Almost surely, 2^51565436240 is an apocalyptic number.

It is an amenable number.

51565436240 is an abundant number, since it is smaller than the sum of its proper divisors (68848969840).

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

51565436240 is a wasteful number, since it uses less digits than its factorization.

51565436240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3340 (or 3334 counting only the distinct ones).

The product of its (nonzero) digits is 432000, while the sum is 41.

The spelling of 51565436240 in words is "fifty-one billion, five hundred sixty-five million, four hundred thirty-six thousand, two hundred forty".