1665043049 has 2 divisors, whose sum is σ = 1665043050. Its totient is φ = 1665043048.

The previous prime is 1665043043. The next prime is 1665043069. The reversal of 1665043049 is 9403405661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1595203600 + 69839449 = 39940^2 + 8357^2 .

It is a cyclic number.

It is not a de Polignac number, because 1665043049 - 2²⁴ = 1648265833 is a prime.

It is not a weakly prime, because it can be changed into another prime (1665043043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 832521524 + 832521525.

It is an arithmetic number, because the mean of its divisors is an integer number (832521525).

Almost surely, 2^1665043049 is an apocalyptic number.

It is an amenable number.

1665043049 is a deficient number, since it is larger than the sum of its proper divisors (1).

1665043049 is an equidigital number, since it uses as much as digits as its factorization.

1665043049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 77760, while the sum is 38.

The square root of 1665043049 is about 40804.9390270345. The cubic root of 1665043049 is about 1185.2459740892.

The spelling of 1665043049 in words is "one billion, six hundred sixty-five million, forty-three thousand, forty-nine".