51205666345 has 8 divisors (see below), whose sum is σ = 61448479560. Its totient is φ = 40963413120.

The previous prime is 51205666271. The next prime is 51205666363. The reversal of 51205666345 is 54366650215.

51205666345 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 894727744 + 50310938601 = 29912^2 + 224301^2 .

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

It is not a de Polignac number, because 51205666345 - 2¹⁷ = 51205535273 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97941 + ... + 334669.

It is an arithmetic number, because the mean of its divisors is an integer number (7681059945).

Almost surely, 2^51205666345 is an apocalyptic number.

It is an amenable number.

51205666345 is a deficient number, since it is larger than the sum of its proper divisors (10242813215).

51205666345 is a wasteful number, since it uses less digits than its factorization.

51205666345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 279995.

The product of its (nonzero) digits is 648000, while the sum is 43.

The spelling of 51205666345 in words is "fifty-one billion, two hundred five million, six hundred sixty-six thousand, three hundred forty-five".