1669441491 has 12 divisors (see below), whose sum is σ = 2413258120. Its totient is φ = 1112110560.

The previous prime is 1669441483. The next prime is 1669441507. The reversal of 1669441491 is 1941449661.

1669441491 is a `hidden beast` number, since 1 + 66 + 94 + 414 + 91 = 666.

1669441491 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1669441491 - 2³ = 1669441483 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1669441451) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 58321 + ... + 82098.

Almost surely, 2^1669441491 is an apocalyptic number.

1669441491 is a deficient number, since it is larger than the sum of its proper divisors (743816629).

1669441491 is a wasteful number, since it uses less digits than its factorization.

1669441491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141746 (or 141743 counting only the distinct ones).

The product of its digits is 186624, while the sum is 45.

The square root of 1669441491 is about 40858.7994317014. The cubic root of 1669441491 is about 1186.2887202824.

It can be divided in two parts, 16694 and 41491, that added together give a palindrome (58185).

The spelling of 1669441491 in words is "one billion, six hundred sixty-nine million, four hundred forty-one thousand, four hundred ninety-one".