1665551545 has 8 divisors (see below), whose sum is σ = 2284185024. Its totient is φ = 1142092464.

The previous prime is 1665551527. The next prime is 1665551561. The reversal of 1665551545 is 5451555661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1665551545 - 2¹³ = 1665543353 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23793559 + ... + 23793628.

It is an arithmetic number, because the mean of its divisors is an integer number (285523128).

Almost surely, 2^1665551545 is an apocalyptic number.

It is an amenable number.

1665551545 is a deficient number, since it is larger than the sum of its proper divisors (618633479).

1665551545 is an equidigital number, since it uses as much as digits as its factorization.

1665551545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47587199.

The product of its digits is 450000, while the sum is 43.

The square root of 1665551545 is about 40811.1693657508. The cubic root of 1665551545 is about 1185.3666179156.

It can be divided in two parts, 166555 and 1545, that added together give a square (168100 = 410²).

The spelling of 1665551545 in words is "one billion, six hundred sixty-five million, five hundred fifty-one thousand, five hundred forty-five".