1221320112001 has 4 divisors (see below), whose sum is σ = 1332349213104. Its totient is φ = 1110291010900.

The previous prime is 1221320111983. The next prime is 1221320112011. The reversal of 1221320112001 is 1002110231221.

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 1221320112001 - 2⁷ = 1221320111873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221320112011) 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, 55514550535 + ... + 55514550556.

It is an arithmetic number, because the mean of its divisors is an integer number (333087303276).

Almost surely, 2^{1221320112001} is an apocalyptic number.

1221320112001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221320112001 is a deficient number, since it is larger than the sum of its proper divisors (111029101103).

1221320112001 is a wasteful number, since it uses less digits than its factorization.

1221320112001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111029101102.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 1221320112001 its reverse (1002110231221), we get a palindrome (2223430343222).

The spelling of 1221320112001 in words is "one trillion, two hundred twenty-one billion, three hundred twenty million, one hundred twelve thousand, one".