1666062606661 has 4 divisors (see below), whose sum is σ = 1666073993632. Its totient is φ = 1666051219692.

The previous prime is 1666062606601. The next prime is 1666062606683.

1666062606661 is nontrivially palindromic in base 10.

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 1666062606661 - 2¹⁷ = 1666062475589 is a prime.

It is a super-3 number, since 3×1666062606661³ (a number of 38 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1666062606599 and 1666062606608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666062606601) 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, 5471121 + ... + 5767606.

It is an arithmetic number, because the mean of its divisors is an integer number (416518498408).

Almost surely, 2^{1666062606661} is an apocalyptic number.

It is an amenable number.

1666062606661 is a deficient number, since it is larger than the sum of its proper divisors (11386971).

1666062606661 is a wasteful number, since it uses less digits than its factorization.

1666062606661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11386970.

The product of its (nonzero) digits is 3359232, while the sum is 52.

The spelling of 1666062606661 in words is "one trillion, six hundred sixty-six billion, sixty-two million, six hundred six thousand, six hundred sixty-one".