1211001000121 has 16 divisors (see below), whose sum is σ = 1377766752768. Its totient is φ = 1054413273600.

The previous prime is 1211001000047. The next prime is 1211001000173. The reversal of 1211001000121 is 1210001001121.

It is a cyclic number.

It is not a de Polignac number, because 1211001000121 - 2¹⁵ = 1211000967353 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1211001000098 and 1211001000107.

It is not an unprimeable number, because it can be changed into a prime (1211001100121) 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, 18272710 + ... + 18338863.

It is an arithmetic number, because the mean of its divisors is an integer number (86110422048).

Almost surely, 2^{1211001000121} is an apocalyptic number.

1211001000121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1211001000121 is a deficient number, since it is larger than the sum of its proper divisors (166765752647).

1211001000121 is a wasteful number, since it uses less digits than its factorization.

1211001000121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36611712.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 1211001000121 its reverse (1210001001121), we get a palindrome (2421002001242).

It can be divided in two parts, 1211001000 and 121, that added together give a palindrome (1211001121).

The spelling of 1211001000121 in words is "one trillion, two hundred eleven billion, one million, one hundred twenty-one", and thus it is an aban number.