1221012101323 has 4 divisors (see below), whose sum is σ = 1395442401520. Its totient is φ = 1046581801128.

The previous prime is 1221012101291. The next prime is 1221012101339. The reversal of 1221012101323 is 3231012101221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1221012101323 - 2⁵ = 1221012101291 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221012101323.

It is not an unprimeable number, because it can be changed into a prime (1221012101423) 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, 87215150088 + ... + 87215150101.

It is an arithmetic number, because the mean of its divisors is an integer number (348860600380).

Almost surely, 2^{1221012101323} is an apocalyptic number.

1221012101323 is a deficient number, since it is larger than the sum of its proper divisors (174430300197).

1221012101323 is an equidigital number, since it uses as much as digits as its factorization.

1221012101323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174430300196.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 1221012101323 its reverse (3231012101221), we get a palindrome (4452024202544).

The spelling of 1221012101323 in words is "one trillion, two hundred twenty-one billion, twelve million, one hundred one thousand, three hundred twenty-three".