2001566165 has 16 divisors (see below), whose sum is σ = 2436134400. Its totient is φ = 1578501312.

The previous prime is 2001566141. The next prime is 2001566201. The reversal of 2001566165 is 5616651002.

It is a cyclic number.

It is not a de Polignac number, because 2001566165 - 2¹⁸ = 2001304021 is a prime.

It is a super-2 number, since 2×2001566165² = 8012534225745614450, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 193751 + ... + 203819.

It is an arithmetic number, because the mean of its divisors is an integer number (152258400).

Almost surely, 2^2001566165 is an apocalyptic number.

It is an amenable number.

2001566165 is a deficient number, since it is larger than the sum of its proper divisors (434568235).

2001566165 is a wasteful number, since it uses less digits than its factorization.

2001566165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10636.

The product of its (nonzero) digits is 10800, while the sum is 32.

The square root of 2001566165 is about 44738.8663803633. The cubic root of 2001566165 is about 1260.2498381289.

The spelling of 2001566165 in words is "two billion, one million, five hundred sixty-six thousand, one hundred sixty-five".