201213391 has 4 divisors (see below), whose sum is σ = 201241800. Its totient is φ = 201184984.

The previous prime is 201213373. The next prime is 201213421. The reversal of 201213391 is 193312102.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201213391 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 (201213301) 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 3 ways as a sum of consecutive naturals, for example, 6000 + ... + 20938.

It is an arithmetic number, because the mean of its divisors is an integer number (50310450).

Almost surely, 2^201213391 is an apocalyptic number.

201213391 is a deficient number, since it is larger than the sum of its proper divisors (28409).

201213391 is a wasteful number, since it uses less digits than its factorization.

201213391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28408.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 201213391 is about 14184.9706027189. The cubic root of 201213391 is about 585.9838228944.

Adding to 201213391 its reverse (193312102), we get a palindrome (394525493).

The spelling of 201213391 in words is "two hundred one million, two hundred thirteen thousand, three hundred ninety-one".