51591065643 has 32 divisors (see below), whose sum is σ = 82369172480. Its totient is φ = 31725730080.

The previous prime is 51591065623. The next prime is 51591065651. The reversal of 51591065643 is 34656019515.

51591065643 is a `hidden beast` number, since 5 + 1 + 591 + 0 + 6 + 56 + 4 + 3 = 666.

It is not a de Polignac number, because 51591065643 - 2²⁰ = 51590017067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51591065623) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 447828 + ... + 551118.

It is an arithmetic number, because the mean of its divisors is an integer number (2574036640).

Almost surely, 2^51591065643 is an apocalyptic number.

51591065643 is a deficient number, since it is larger than the sum of its proper divisors (30778106837).

51591065643 is a wasteful number, since it uses less digits than its factorization.

51591065643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104736 (or 104730 counting only the distinct ones).

The product of its (nonzero) digits is 486000, while the sum is 45.

The spelling of 51591065643 in words is "fifty-one billion, five hundred ninety-one million, sixty-five thousand, six hundred forty-three".