51666435445 has 16 divisors (see below), whose sum is σ = 66722948208. Its totient is φ = 38264048640.

The previous prime is 51666435421. The next prime is 51666435487. The reversal of 51666435445 is 54453466615.

It can be written as a sum of positive squares in 8 ways, for example, as 40233649 + 51626201796 = 6343^2 + 227214^2 .

It is not a de Polignac number, because 51666435445 - 2¹¹ = 51666433397 is a prime.

It is a super-3 number, since 3×51666435445³ (a number of 33 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4977114 + ... + 4987483.

It is an arithmetic number, because the mean of its divisors is an integer number (4170184263).

Almost surely, 2^51666435445 is an apocalyptic number.

It is an amenable number.

51666435445 is a deficient number, since it is larger than the sum of its proper divisors (15056512763).

51666435445 is a wasteful number, since it uses less digits than its factorization.

51666435445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9964680.

The product of its digits is 5184000, while the sum is 49.

The spelling of 51666435445 in words is "fifty-one billion, six hundred sixty-six million, four hundred thirty-five thousand, four hundred forty-five".