201662191 has 4 divisors (see below), whose sum is σ = 205467192. Its totient is φ = 197857192.

The previous prime is 201662171. The next prime is 201662203. The reversal of 201662191 is 191266102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 201662191 - 2²¹ = 199565039 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201662141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1902421 + ... + 1902526.

It is an arithmetic number, because the mean of its divisors is an integer number (51366798).

Almost surely, 2^201662191 is an apocalyptic number.

201662191 is a deficient number, since it is larger than the sum of its proper divisors (3805001).

201662191 is an equidigital number, since it uses as much as digits as its factorization.

201662191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3805000.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 201662191 is about 14200.7813517426. The cubic root of 201662191 is about 586.4191720701.

The spelling of 201662191 in words is "two hundred one million, six hundred sixty-two thousand, one hundred ninety-one".