1221321241 has 16 divisors (see below), whose sum is σ = 1427652864. Its totient is φ = 1023107904.

The previous prime is 1221321239. The next prime is 1221321247. The reversal of 1221321241 is 1421231221.

It is not a de Polignac number, because 1221321241 - 2¹ = 1221321239 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221321247) 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, 91315 + ... + 103831.

It is an arithmetic number, because the mean of its divisors is an integer number (89228304).

Almost surely, 2^1221321241 is an apocalyptic number.

It is an amenable number.

1221321241 is a deficient number, since it is larger than the sum of its proper divisors (206331623).

1221321241 is a wasteful number, since it uses less digits than its factorization.

1221321241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12840.

The product of its digits is 192, while the sum is 19.

The square root of 1221321241 is about 34947.4067850535. The cubic root of 1221321241 is about 1068.9153246703.

Adding to 1221321241 its reverse (1421231221), we get a palindrome (2642552462).

The spelling of 1221321241 in words is "one billion, two hundred twenty-one million, three hundred twenty-one thousand, two hundred forty-one".