52666501661 has 4 divisors (see below), whose sum is σ = 53951050524. Its totient is φ = 51381952800.

The previous prime is 52666501651. The next prime is 52666501703. The reversal of 52666501661 is 16610566625.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 6529609636 + 46136892025 = 80806^2 + 214795^2 .

It is a cyclic number.

It is not a de Polignac number, because 52666501661 - 2¹⁰ = 52666500637 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 (52666501651) 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, 642274370 + ... + 642274451.

It is an arithmetic number, because the mean of its divisors is an integer number (13487762631).

Almost surely, 2^52666501661 is an apocalyptic number.

It is an amenable number.

52666501661 is a deficient number, since it is larger than the sum of its proper divisors (1284548863).

52666501661 is a wasteful number, since it uses less digits than its factorization.

52666501661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1284548862.

The product of its (nonzero) digits is 388800, while the sum is 44.

The spelling of 52666501661 in words is "fifty-two billion, six hundred sixty-six million, five hundred one thousand, six hundred sixty-one".