43521201131221 has 16 divisors (see below), whose sum is σ = 47497507496640. Its totient is φ = 39548202052480.

The previous prime is 43521201131203. The next prime is 43521201131299. The reversal of 43521201131221 is 12213110212534.

It is not a de Polignac number, because 43521201131221 - 2⁹ = 43521201130709 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 43521201131221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43521201141221) 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, 761111010 + ... + 761168188.

It is an arithmetic number, because the mean of its divisors is an integer number (2968594218540).

Almost surely, 2^{43521201131221} is an apocalyptic number.

It is an amenable number.

43521201131221 is a deficient number, since it is larger than the sum of its proper divisors (3976306365419).

43521201131221 is a wasteful number, since it uses less digits than its factorization.

43521201131221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84884.

The product of its (nonzero) digits is 2880, while the sum is 28.

Adding to 43521201131221 its reverse (12213110212534), we get a palindrome (55734311343755).

The spelling of 43521201131221 in words is "forty-three trillion, five hundred twenty-one billion, two hundred one million, one hundred thirty-one thousand, two hundred twenty-one".