1221332331 has 16 divisors (see below), whose sum is σ = 1715696640. Its totient is φ = 770672160.

The previous prime is 1221332263. The next prime is 1221332339. The reversal of 1221332331 is 1332331221.

It is not a de Polignac number, because 1221332331 - 2⁹ = 1221331819 is a prime.

It is a super-2 number, since 2×1221332331² = 2983305325491787122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1221332298 and 1221332307.

It is not an unprimeable number, because it can be changed into a prime (1221332339) 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, 58246 + ... + 76388.

It is an arithmetic number, because the mean of its divisors is an integer number (107231040).

Almost surely, 2^1221332331 is an apocalyptic number.

1221332331 is a deficient number, since it is larger than the sum of its proper divisors (494364309).

1221332331 is a wasteful number, since it uses less digits than its factorization.

1221332331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19346.

The product of its digits is 648, while the sum is 21.

The square root of 1221332331 is about 34947.5654516878. The cubic root of 1221332331 is about 1068.9185600285.

Adding to 1221332331 its reverse (1332331221), we get a palindrome (2553663552).

It can be divided in two parts, 12213 and 32331, that added together give a palindrome (44544).

The spelling of 1221332331 in words is "one billion, two hundred twenty-one million, three hundred thirty-two thousand, three hundred thirty-one".