1221341331 has 16 divisors (see below), whose sum is σ = 1942009344. Its totient is φ = 667565184.

The previous prime is 1221341327. The next prime is 1221341411. The reversal of 1221341331 is 1331431221.

It is not a de Polignac number, because 1221341331 - 2² = 1221341327 is a prime.

It is a super-2 number, since 2×1221341331² = 2983349293617703122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 1221341298 and 1221341307.

It is not an unprimeable number, because it can be changed into a prime (1221341311) 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, 1263846 + ... + 1264811.

It is an arithmetic number, because the mean of its divisors is an integer number (121375584).

Almost surely, 2^1221341331 is an apocalyptic number.

1221341331 is a deficient number, since it is larger than the sum of its proper divisors (720668013).

1221341331 is a wasteful number, since it uses less digits than its factorization.

1221341331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2528690.

The product of its digits is 432, while the sum is 21.

The square root of 1221341331 is about 34947.6942157848. The cubic root of 1221341331 is about 1068.9211856429.

Adding to 1221341331 its reverse (1331431221), we get a palindrome (2552772552).

The spelling of 1221341331 in words is "one billion, two hundred twenty-one million, three hundred forty-one thousand, three hundred thirty-one".