1213521412121 has 4 divisors (see below), whose sum is σ = 1266283212672. Its totient is φ = 1160759611572.

The previous prime is 1213521412079. The next prime is 1213521412151. The reversal of 1213521412121 is 1212141253121.

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 a de Polignac number, because none of the positive numbers 2^k-1213521412121 is a prime.

It is a super-2 number, since 2×1213521412121² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1213521412151) 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, 26380900241 + ... + 26380900286.

It is an arithmetic number, because the mean of its divisors is an integer number (316570803168).

Almost surely, 2^{1213521412121} is an apocalyptic number.

It is an amenable number.

1213521412121 is a deficient number, since it is larger than the sum of its proper divisors (52761800551).

1213521412121 is an equidigital number, since it uses as much as digits as its factorization.

1213521412121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52761800550.

The product of its digits is 960, while the sum is 26.

Adding to 1213521412121 its reverse (1212141253121), we get a palindrome (2425662665242).

The spelling of 1213521412121 in words is "one trillion, two hundred thirteen billion, five hundred twenty-one million, four hundred twelve thousand, one hundred twenty-one".