201719491 has 2 divisors, whose sum is σ = 201719492. Its totient is φ = 201719490.

The previous prime is 201719489. The next prime is 201719527. The reversal of 201719491 is 194917102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 201719491 - 2¹ = 201719489 is a prime.

Together with 201719489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (201719191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100859745 + 100859746.

It is an arithmetic number, because the mean of its divisors is an integer number (100859746).

Almost surely, 2^201719491 is an apocalyptic number.

201719491 is a deficient number, since it is larger than the sum of its proper divisors (1).

201719491 is an equidigital number, since it uses as much as digits as its factorization.

201719491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4536, while the sum is 34.

The square root of 201719491 is about 14202.7987030726. The cubic root of 201719491 is about 586.4747082391.

The spelling of 201719491 in words is "two hundred one million, seven hundred nineteen thousand, four hundred ninety-one".