1665051653 has 4 divisors (see below), whose sum is σ = 1665879180. Its totient is φ = 1664224128.

The previous prime is 1665051611. The next prime is 1665051659. The reversal of 1665051653 is 3561505661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1264371364 + 400680289 = 35558^2 + 20017^2 .

It is a cyclic number.

It is not a de Polignac number, because 1665051653 - 2⁶ = 1665051589 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1665051659) 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, 410738 + ... + 414771.

It is an arithmetic number, because the mean of its divisors is an integer number (416469795).

Almost surely, 2^1665051653 is an apocalyptic number.

It is an amenable number.

1665051653 is a deficient number, since it is larger than the sum of its proper divisors (827527).

1665051653 is an equidigital number, since it uses as much as digits as its factorization.

1665051653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 827526.

The product of its (nonzero) digits is 81000, while the sum is 38.

The square root of 1665051653 is about 40805.0444553121. The cubic root of 1665051653 is about 1185.2480156457.

The spelling of 1665051653 in words is "one billion, six hundred sixty-five million, fifty-one thousand, six hundred fifty-three".