121221121201111 has 16 divisors (see below), whose sum is σ = 123851205319680. Its totient is φ = 118593165509280.

The previous prime is 121221121201099. The next prime is 121221121201121. The reversal of 121221121201111 is 111102121122121.

It is a cyclic number.

It is not a de Polignac number, because 121221121201111 - 2²⁵ = 121221087646679 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221121201121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1999955196 + ... + 2000015806.

It is an arithmetic number, because the mean of its divisors is an integer number (7740700332480).

Almost surely, 2^{121221121201111} is an apocalyptic number.

121221121201111 is a deficient number, since it is larger than the sum of its proper divisors (2630084118569).

121221121201111 is a wasteful number, since it uses less digits than its factorization.

121221121201111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77454.

The product of its (nonzero) digits is 32, while the sum is 19.

Adding to 121221121201111 its reverse (111102121122121), we get a palindrome (232323242323232).

The spelling of 121221121201111 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, one hundred twenty-one million, two hundred one thousand, one hundred eleven".