201209391 has 12 divisors (see below), whose sum is σ = 291127200. Its totient is φ = 133912800.

The previous prime is 201209387. The next prime is 201209413. The reversal of 201209391 is 193902102.

It is not a de Polignac number, because 201209391 - 2² = 201209387 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201209891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13191 + ... + 24008.

It is an arithmetic number, because the mean of its divisors is an integer number (24260600).

Almost surely, 2^201209391 is an apocalyptic number.

201209391 is a deficient number, since it is larger than the sum of its proper divisors (89917809).

201209391 is a wasteful number, since it uses less digits than its factorization.

201209391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37806 (or 37803 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 201209391 is about 14184.8296077182. The cubic root of 201209391 is about 585.9799398678.

The spelling of 201209391 in words is "two hundred one million, two hundred nine thousand, three hundred ninety-one".