1221231167321 has 4 divisors (see below), whose sum is σ = 1332252182544. Its totient is φ = 1110210152100.

The previous prime is 1221231167297. The next prime is 1221231167383. The reversal of 1221231167321 is 1237611321221.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1221231167321 - 2¹⁸ = 1221230905177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221230167321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55510507595 + ... + 55510507616.

It is an arithmetic number, because the mean of its divisors is an integer number (333063045636).

Almost surely, 2^{1221231167321} is an apocalyptic number.

1221231167321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221231167321 is a deficient number, since it is larger than the sum of its proper divisors (111021015223).

1221231167321 is a wasteful number, since it uses less digits than its factorization.

1221231167321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111021015222.

The product of its digits is 6048, while the sum is 32.

Adding to 1221231167321 its reverse (1237611321221), we get a palindrome (2458842488542).

The spelling of 1221231167321 in words is "one trillion, two hundred twenty-one billion, two hundred thirty-one million, one hundred sixty-seven thousand, three hundred twenty-one".