201690217 has 4 divisors (see below), whose sum is σ = 204996676. Its totient is φ = 198383760.

The previous prime is 201690199. The next prime is 201690271. The reversal of 201690217 is 712096102.

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 15531481 + 186158736 = 3941^2 + 13644^2 .

It is a cyclic number.

It is not a de Polignac number, because 201690217 - 2²³ = 193301609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201690277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1653138 + ... + 1653259.

It is an arithmetic number, because the mean of its divisors is an integer number (51249169).

Almost surely, 2^201690217 is an apocalyptic number.

It is an amenable number.

201690217 is a deficient number, since it is larger than the sum of its proper divisors (3306459).

201690217 is an equidigital number, since it uses as much as digits as its factorization.

201690217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3306458.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 201690217 is about 14201.7680941494. The cubic root of 201690217 is about 586.4463366770.

The spelling of 201690217 in words is "two hundred one million, six hundred ninety thousand, two hundred seventeen".