51631064640221 has 8 divisors (see below), whose sum is σ = 56325757850688. Its totient is φ = 46936531440000.

The previous prime is 51631064640203. The next prime is 51631064640301. The reversal of 51631064640221 is 12204646013615.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51631064640221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51631064642221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39327380 + ... + 40619021.

It is an arithmetic number, because the mean of its divisors is an integer number (7040719731336).

Almost surely, 2^{51631064640221} is an apocalyptic number.

It is an amenable number.

51631064640221 is a deficient number, since it is larger than the sum of its proper divisors (4694693210467).

51631064640221 is a wasteful number, since it uses less digits than its factorization.

51631064640221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80005123.

The product of its (nonzero) digits is 207360, while the sum is 41.

The spelling of 51631064640221 in words is "fifty-one trillion, six hundred thirty-one billion, sixty-four million, six hundred forty thousand, two hundred twenty-one".