201721613 has 16 divisors (see below), whose sum is σ = 215688000. Its totient is φ = 188116992.

The previous prime is 201721601. The next prime is 201721627. The reversal of 201721613 is 316127102.

It is a cyclic number.

It is not a de Polignac number, because 201721613 - 2⁶ = 201721549 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201721673) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 532058 + ... + 532436.

It is an arithmetic number, because the mean of its divisors is an integer number (13480500).

Almost surely, 2^201721613 is an apocalyptic number.

It is an amenable number.

201721613 is a deficient number, since it is larger than the sum of its proper divisors (13966387).

201721613 is a wasteful number, since it uses less digits than its factorization.

201721613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 764.

The product of its (nonzero) digits is 504, while the sum is 23.

The square root of 201721613 is about 14202.8734064625. The cubic root of 201721613 is about 586.4767647169.

Adding to 201721613 its reverse (316127102), we get a palindrome (517848715).

The spelling of 201721613 in words is "two hundred one million, seven hundred twenty-one thousand, six hundred thirteen".