1001655565 has 4 divisors (see below), whose sum is σ = 1201986684. Its totient is φ = 801324448.

The previous prime is 1001655559. The next prime is 1001655619. The reversal of 1001655565 is 5655561001.

1001655565 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5655561001 = 10039 ⋅563359.

It can be written as a sum of positive squares in 2 ways, for example, as 107765161 + 893890404 = 10381^2 + 29898^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001655565 - 2¹³ = 1001647373 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1001655565.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 100165552 + ... + 100165561.

It is an arithmetic number, because the mean of its divisors is an integer number (300496671).

Almost surely, 2^1001655565 is an apocalyptic number.

It is an amenable number.

1001655565 is a deficient number, since it is larger than the sum of its proper divisors (200331119).

1001655565 is an equidigital number, since it uses as much as digits as its factorization.

1001655565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200331118.

The product of its (nonzero) digits is 22500, while the sum is 34.

The square root of 1001655565 is about 31648.9425573746. The cubic root of 1001655565 is about 1000.5515507359.

The spelling of 1001655565 in words is "one billion, one million, six hundred fifty-five thousand, five hundred sixty-five".