3121430221 has 32 divisors (see below), whose sum is σ = 3903065600. Its totient is φ = 2430590976.

The previous prime is 3121430209. The next prime is 3121430267. The reversal of 3121430221 is 1220341213.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 3121430221 - 2⁵ = 3121430189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3121430201) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1755685 + ... + 1757461.

It is an arithmetic number, because the mean of its divisors is an integer number (121970800).

Almost surely, 2^3121430221 is an apocalyptic number.

It is an amenable number.

3121430221 is a deficient number, since it is larger than the sum of its proper divisors (781635379).

3121430221 is a wasteful number, since it uses less digits than its factorization.

3121430221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2093.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 3121430221 is about 55869.7612398693. The cubic root of 3121430221 is about 1461.4519584812.

Adding to 3121430221 its reverse (1220341213), we get a palindrome (4341771434).

The spelling of 3121430221 in words is "three billion, one hundred twenty-one million, four hundred thirty thousand, two hundred twenty-one".