1521441221 has 8 divisors (see below), whose sum is σ = 1563095040. Its totient is φ = 1479815568.

The previous prime is 1521441209. The next prime is 1521441227. The reversal of 1521441221 is 1221441251.

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 1521441221 - 2¹⁰ = 1521440197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1521441227) 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, 148940 + ... + 158826.

It is an arithmetic number, because the mean of its divisors is an integer number (195386880).

Almost surely, 2^1521441221 is an apocalyptic number.

It is an amenable number.

1521441221 is a deficient number, since it is larger than the sum of its proper divisors (41653819).

1521441221 is an equidigital number, since it uses as much as digits as its factorization.

1521441221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14083.

The product of its digits is 640, while the sum is 23.

The square root of 1521441221 is about 39005.6562693156. The cubic root of 1521441221 is about 1150.1426971006.

Adding to 1521441221 its reverse (1221441251), we get a palindrome (2742882472).

The spelling of 1521441221 in words is "one billion, five hundred twenty-one million, four hundred forty-one thousand, two hundred twenty-one".