51649278729907 has 4 divisors (see below), whose sum is σ = 51649317050896. Its totient is φ = 51649240408920.

The previous prime is 51649278729863. The next prime is 51649278729943. The reversal of 51649278729907 is 70992787294615.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51649278729907 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51649278729407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17062188 + ... + 19859929.

It is an arithmetic number, because the mean of its divisors is an integer number (12912329262724).

Almost surely, 2^{51649278729907} is an apocalyptic number.

51649278729907 is a deficient number, since it is larger than the sum of its proper divisors (38320989).

51649278729907 is a wasteful number, since it uses less digits than its factorization.

51649278729907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38320988.

The product of its (nonzero) digits is 960180480, while the sum is 76.

The spelling of 51649278729907 in words is "fifty-one trillion, six hundred forty-nine billion, two hundred seventy-eight million, seven hundred twenty-nine thousand, nine hundred seven".