1669669661 has 16 divisors (see below), whose sum is σ = 1887452160. Its totient is φ = 1463782320.

The previous prime is 1669669627. The next prime is 1669669663.

1669669661 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1669669661 - 2⁶ = 1669669597 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1669669597 and 1669669606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1669669663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15026 + ... + 59708.

It is an arithmetic number, because the mean of its divisors is an integer number (117965760).

Almost surely, 2^1669669661 is an apocalyptic number.

1669669661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1669669661 is a deficient number, since it is larger than the sum of its proper divisors (217782499).

1669669661 is a wasteful number, since it uses less digits than its factorization.

1669669661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44816.

The product of its digits is 3779136, while the sum is 56.

The square root of 1669669661 is about 40861.5915133026. The cubic root of 1669669661 is about 1186.3427629405.

The spelling of 1669669661 in words is "one billion, six hundred sixty-nine million, six hundred sixty-nine thousand, six hundred sixty-one".