1221131123099 has 4 divisors (see below), whose sum is σ = 1221158875440. Its totient is φ = 1221103370760.

The previous prime is 1221131123083. The next prime is 1221131123119. The reversal of 1221131123099 is 9903211311221.

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 1221131123099 - 2⁴ = 1221131123083 is a prime.

It is a super-2 number, since 2×1221131123099² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221131123039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13810064 + ... + 13898205.

It is an arithmetic number, because the mean of its divisors is an integer number (305289718860).

Almost surely, 2^{1221131123099} is an apocalyptic number.

1221131123099 is a deficient number, since it is larger than the sum of its proper divisors (27752341).

1221131123099 is an equidigital number, since it uses as much as digits as its factorization.

1221131123099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27752340.

The product of its (nonzero) digits is 5832, while the sum is 35.

The spelling of 1221131123099 in words is "one trillion, two hundred twenty-one billion, one hundred thirty-one million, one hundred twenty-three thousand, ninety-nine".