51216160721 has 8 divisors (see below), whose sum is σ = 55875729504. Its totient is φ = 46557184320.

The previous prime is 51216160673. The next prime is 51216160741. The reversal of 51216160721 is 12706161215.

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

It is a cyclic number.

It is not a de Polignac number, because 51216160721 - 2²⁶ = 51149051857 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (51216160741) 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, 43466 + ... + 322988.

It is an arithmetic number, because the mean of its divisors is an integer number (6984466188).

Almost surely, 2^51216160721 is an apocalyptic number.

It is an amenable number.

51216160721 is a deficient number, since it is larger than the sum of its proper divisors (4659568783).

51216160721 is a wasteful number, since it uses less digits than its factorization.

51216160721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296191.

The product of its (nonzero) digits is 5040, while the sum is 32.

The spelling of 51216160721 in words is "fifty-one billion, two hundred sixteen million, one hundred sixty thousand, seven hundred twenty-one".