666553346140261 has 8 divisors (see below), whose sum is σ = 668216631610584. Its totient is φ = 664890065932800.

The previous prime is 666553346140249. The next prime is 666553346140267. The reversal of 666553346140261 is 162041643355666.

666553346140261 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 493745731752100 + 172807614388161 = 22220390^2 + 13145631^2 .

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 666553346140261 - 2¹⁷ = 666553346009189 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 666553346140196 and 666553346140205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666553346140267) 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, 421894795 + ... + 423471751.

It is an arithmetic number, because the mean of its divisors is an integer number (83527078951323).

Almost surely, 2^{666553346140261} is an apocalyptic number.

It is an amenable number.

666553346140261 is a deficient number, since it is larger than the sum of its proper divisors (1663285470323).

666553346140261 is a wasteful number, since it uses less digits than its factorization.

666553346140261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2631431.

The product of its (nonzero) digits is 55987200, while the sum is 58.

The spelling of 666553346140261 in words is "six hundred sixty-six trillion, five hundred fifty-three billion, three hundred forty-six million, one hundred forty thousand, two hundred sixty-one".