201540551521 has 8 divisors (see below), whose sum is σ = 207148973184. Its totient is φ = 195940623600.

The previous prime is 201540551497. The next prime is 201540551533. The reversal of 201540551521 is 125155045102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 201540551521 - 2¹⁹ = 201540027233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201540501521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2075305 + ... + 2170246.

It is an arithmetic number, because the mean of its divisors is an integer number (25893621648).

Almost surely, 2^201540551521 is an apocalyptic number.

It is an amenable number.

201540551521 is a deficient number, since it is larger than the sum of its proper divisors (5608421663).

201540551521 is a wasteful number, since it uses less digits than its factorization.

201540551521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4246871.

The product of its (nonzero) digits is 10000, while the sum is 31.

Adding to 201540551521 its reverse (125155045102), we get a palindrome (326695596623).

The spelling of 201540551521 in words is "two hundred one billion, five hundred forty million, five hundred fifty-one thousand, five hundred twenty-one".