3721221111221 has 8 divisors (see below), whose sum is σ = 3932165402880. Its totient is φ = 3514372825392.

The previous prime is 3721221111199. The next prime is 3721221111229. The reversal of 3721221111221 is 1221111221273.

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 3721221111221 - 2¹⁰ = 3721221110197 is a prime.

It is a super-2 number, since 2×3721221111221² (a number of 26 digits) contains 22 as substring.

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 (3721221111229) 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, 1023999590 + ... + 1024003223.

It is an arithmetic number, because the mean of its divisors is an integer number (491520675360).

Almost surely, 2^{3721221111221} is an apocalyptic number.

It is an amenable number.

3721221111221 is a deficient number, since it is larger than the sum of its proper divisors (210944291659).

3721221111221 is a wasteful number, since it uses less digits than its factorization.

3721221111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2048002915.

The product of its digits is 672, while the sum is 26.

Adding to 3721221111221 its reverse (1221111221273), we get a palindrome (4942332332494).

The spelling of 3721221111221 in words is "three trillion, seven hundred twenty-one billion, two hundred twenty-one million, one hundred eleven thousand, two hundred twenty-one".