1211101112121 has 4 divisors (see below), whose sum is σ = 1614801482832. Its totient is φ = 807400741412.

The previous prime is 1211101112107. The next prime is 1211101112131. The reversal of 1211101112121 is 1212111011121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1211101112121 - 2⁷ = 1211101111993 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1211101112121.

It is not an unprimeable number, because it can be changed into a prime (1211101112131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 201850185351 + ... + 201850185356.

It is an arithmetic number, because the mean of its divisors is an integer number (403700370708).

Almost surely, 2^{1211101112121} is an apocalyptic number.

It is an amenable number.

1211101112121 is a deficient number, since it is larger than the sum of its proper divisors (403700370711).

1211101112121 is an equidigital number, since it uses as much as digits as its factorization.

1211101112121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 403700370710.

The product of its (nonzero) digits is 8, while the sum is 15.

Adding to 1211101112121 its reverse (1212111011121), we get a palindrome (2423212123242).

The spelling of 1211101112121 in words is "one trillion, two hundred eleven billion, one hundred one million, one hundred twelve thousand, one hundred twenty-one".