121221012111 has 16 divisors (see below), whose sum is σ = 170298585600. Its totient is φ = 76486915008.

The previous prime is 121221012109. The next prime is 121221012113. The reversal of 121221012111 is 111210122121.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (121221012109) and next prime (121221012113).

It is not a de Polignac number, because 121221012111 - 2¹ = 121221012109 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221012113) 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, 964206 + ... + 1082651.

It is an arithmetic number, because the mean of its divisors is an integer number (10643661600).

Almost surely, 2^121221012111 is an apocalyptic number.

121221012111 is a deficient number, since it is larger than the sum of its proper divisors (49077573489).

121221012111 is a wasteful number, since it uses less digits than its factorization.

121221012111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2047918.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 121221012111 its reverse (111210122121), we get a palindrome (232431134232).

The spelling of 121221012111 in words is "one hundred twenty-one billion, two hundred twenty-one million, twelve thousand, one hundred eleven".