1669784769 has 27 divisors (see below), whose sum is σ = 2467880233. Its totient is φ = 1087936512.

The previous prime is 1669784759. The next prime is 1669784773. The reversal of 1669784769 is 9674879661.

The square root of 1669784769 is 40863.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 1007237169 + 662547600 = 31737^2 + 25740^2 .

It is not a de Polignac number, because 1669784769 - 2⁹ = 1669784257 is a prime.

It is a super-2 number, since 2×1669784769² = 5576362349568766722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1669784759) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 6497089 + ... + 6497345.

Almost surely, 2^1669784769 is an apocalyptic number.

1669784769 is the 40863-rd square number.

1669784769 is the 20432-nd centered octagonal number.

It is an amenable number.

1669784769 is a deficient number, since it is larger than the sum of its proper divisors (798095464).

1669784769 is an frugal number, since it uses more digits than its factorization.

1669784769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 626 (or 313 counting only the distinct ones).

The product of its digits is 27433728, while the sum is 63.

The cubic root of 1669784769 is about 1186.3700247013.

The spelling of 1669784769 in words is "one billion, six hundred sixty-nine million, seven hundred eighty-four thousand, seven hundred sixty-nine".