201642521 has 4 divisors (see below), whose sum is σ = 202656000. Its totient is φ = 200629044.

The previous prime is 201642517. The next prime is 201642547. The reversal of 201642521 is 125246102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 201642521 - 2² = 201642517 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201642821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 506441 + ... + 506838.

It is an arithmetic number, because the mean of its divisors is an integer number (50664000).

Almost surely, 2^201642521 is an apocalyptic number.

It is an amenable number.

201642521 is a deficient number, since it is larger than the sum of its proper divisors (1013479).

201642521 is a wasteful number, since it uses less digits than its factorization.

201642521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1013478.

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 201642521 is about 14200.0887673282. The cubic root of 201642521 is about 586.4001051343.

Adding to 201642521 its reverse (125246102), we get a palindrome (326888623).

The spelling of 201642521 in words is "two hundred one million, six hundred forty-two thousand, five hundred twenty-one".