2006661303857 has 4 divisors (see below), whose sum is σ = 2293327204416. Its totient is φ = 1719995403300.

The previous prime is 2006661303739. The next prime is 2006661303869. The reversal of 2006661303857 is 7583031666002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2006661303857 - 2⁸ = 2006661303601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2006661303877) 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, 143332950269 + ... + 143332950282.

It is an arithmetic number, because the mean of its divisors is an integer number (573331801104).

Almost surely, 2^{2006661303857} is an apocalyptic number.

It is an amenable number.

2006661303857 is a deficient number, since it is larger than the sum of its proper divisors (286665900559).

2006661303857 is an equidigital number, since it uses as much as digits as its factorization.

2006661303857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 286665900558.

The product of its (nonzero) digits is 1088640, while the sum is 47.

Adding to 2006661303857 its reverse (7583031666002), we get a palindrome (9589692969859).

The spelling of 2006661303857 in words is "two trillion, six billion, six hundred sixty-one million, three hundred three thousand, eight hundred fifty-seven".