1211201213121 has 24 divisors (see below), whose sum is σ = 1752652434624. Its totient is φ = 806018986080.

The previous prime is 1211201213113. The next prime is 1211201213129. The reversal of 1211201213121 is 1213121021121.

It is a happy number.

1211201213121 is a `hidden beast` number, since 1 + 211 + 20 + 121 + 312 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (1211201213113) and next prime (1211201213129).

It is not a de Polignac number, because 1211201213121 - 2³ = 1211201213113 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1211201213094 and 1211201213103.

It is not an unprimeable number, because it can be changed into a prime (1211201213129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 30857110 + ... + 30896336.

It is an arithmetic number, because the mean of its divisors is an integer number (73027184776).

Almost surely, 2^{1211201213121} is an apocalyptic number.

It is an amenable number.

1211201213121 is a deficient number, since it is larger than the sum of its proper divisors (541451221503).

1211201213121 is a wasteful number, since it uses less digits than its factorization.

1211201213121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45301 (or 45298 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 18.

Adding to 1211201213121 its reverse (1213121021121), we get a palindrome (2424322234242).

The spelling of 1211201213121 in words is "one trillion, two hundred eleven billion, two hundred one million, two hundred thirteen thousand, one hundred twenty-one".