3504211221221 has 4 divisors (see below), whose sum is σ = 3543584381100. Its totient is φ = 3464838061344.

The previous prime is 3504211221197. The next prime is 3504211221299. The reversal of 3504211221221 is 1221221124053.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2431151416225 + 1073059804996 = 1559215^2 + 1035886^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3504211221221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3504211221521) 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, 19686579806 + ... + 19686579983.

It is an arithmetic number, because the mean of its divisors is an integer number (885896095275).

Almost surely, 2^{3504211221221} is an apocalyptic number.

It is an amenable number.

3504211221221 is a deficient number, since it is larger than the sum of its proper divisors (39373159879).

3504211221221 is an equidigital number, since it uses as much as digits as its factorization.

3504211221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39373159878.

The product of its (nonzero) digits is 1920, while the sum is 26.

Adding to 3504211221221 its reverse (1221221124053), we get a palindrome (4725432345274).

The spelling of 3504211221221 in words is "three trillion, five hundred four billion, two hundred eleven million, two hundred twenty-one thousand, two hundred twenty-one".