2168001565 has 4 divisors (see below), whose sum is σ = 2601601884. Its totient is φ = 1734401248.

The previous prime is 2168001559. The next prime is 2168001581. The reversal of 2168001565 is 5651008612.

It is a happy number.

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 1130775129 + 1037226436 = 33627^2 + 32206^2 .

It is a cyclic number.

It is not a de Polignac number, because 2168001565 - 2³ = 2168001557 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 2168001565.

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, 216800152 + ... + 216800161.

It is an arithmetic number, because the mean of its divisors is an integer number (650400471).

Almost surely, 2^2168001565 is an apocalyptic number.

It is an amenable number.

2168001565 is a deficient number, since it is larger than the sum of its proper divisors (433600319).

2168001565 is an equidigital number, since it uses as much as digits as its factorization.

2168001565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 433600318.

The product of its (nonzero) digits is 14400, while the sum is 34.

The square root of 2168001565 is about 46561.8037129147. The cubic root of 2168001565 is about 1294.2550368171.

The spelling of 2168001565 in words is "two billion, one hundred sixty-eight million, one thousand, five hundred sixty-five".