121221011009 has 32 divisors (see below), whose sum is σ = 149310750720. Its totient is φ = 96096103488.

The previous prime is 121221010979. The next prime is 121221011059. The reversal of 121221011009 is 900110122121.

It is not a de Polignac number, because 121221011009 - 2⁸ = 121221010753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121221011059) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2457224 + ... + 2506070.

It is an arithmetic number, because the mean of its divisors is an integer number (4665960960).

Almost surely, 2^121221011009 is an apocalyptic number.

121221011009 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

121221011009 is a deficient number, since it is larger than the sum of its proper divisors (28089739711).

121221011009 is a wasteful number, since it uses less digits than its factorization.

121221011009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49317.

The product of its (nonzero) digits is 72, while the sum is 20.

The spelling of 121221011009 in words is "one hundred twenty-one billion, two hundred twenty-one million, eleven thousand, nine".