201986665 has 8 divisors (see below), whose sum is σ = 242630280. Its totient is φ = 161425152.

The previous prime is 201986641. The next prime is 201986671. The reversal of 201986665 is 566689102.

It can be written as a sum of positive squares in 4 ways, for example, as 26132544 + 175854121 = 5112^2 + 13261^2 .

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 201986665 - 2⁹ = 201986153 is a prime.

It is a super-2 number, since 2×201986665² = 81597225675644450, which contains 22 as substring.

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, 14974 + ... + 25063.

It is an arithmetic number, because the mean of its divisors is an integer number (30328785).

Almost surely, 2^201986665 is an apocalyptic number.

It is an amenable number.

201986665 is a deficient number, since it is larger than the sum of its proper divisors (40643615).

201986665 is a wasteful number, since it uses less digits than its factorization.

201986665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41051.

The product of its (nonzero) digits is 155520, while the sum is 43.

The square root of 201986665 is about 14212.2012721464. The cubic root of 201986665 is about 586.7335192340.

The spelling of 201986665 in words is "two hundred one million, nine hundred eighty-six thousand, six hundred sixty-five".