121001001111 has 12 divisors (see below), whose sum is σ = 174783998688. Its totient is φ = 80665130304.

The previous prime is 121001001071. The next prime is 121001001113. The reversal of 121001001111 is 111100100121.

It is not a de Polignac number, because 121001001111 - 2¹⁸ = 121000738967 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 121001001093 and 121001001102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121001001113) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 208066 + ... + 534128.

It is an arithmetic number, because the mean of its divisors is an integer number (14565333224).

Almost surely, 2^121001001111 is an apocalyptic number.

121001001111 is a deficient number, since it is larger than the sum of its proper divisors (53782997577).

121001001111 is a wasteful number, since it uses less digits than its factorization.

121001001111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 367302 (or 367299 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 9.

Adding to 121001001111 its reverse (111100100121), we get a palindrome (232101101232).

The spelling of 121001001111 in words is "one hundred twenty-one billion, one million, one thousand, one hundred eleven".