1212212112021 has 6 divisors (see below), whose sum is σ = 1750973050710. Its totient is φ = 808141408008.

The previous prime is 1212212111989. The next prime is 1212212112031. The reversal of 1212212112021 is 1202112122121.

It can be written as a sum of positive squares in only one way, i.e., 1098534572100 + 113677539921 = 1048110^2 + 337161^2 .

It is not a de Polignac number, because 1212212112021 - 2⁵ = 1212212111989 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1212212111985 and 1212212112003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212212112031) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 67345117326 + ... + 67345117343.

It is an arithmetic number, because the mean of its divisors is an integer number (291828841785).

Almost surely, 2^{1212212112021} is an apocalyptic number.

It is an amenable number.

1212212112021 is a deficient number, since it is larger than the sum of its proper divisors (538760938689).

1212212112021 is a wasteful number, since it uses less digits than its factorization.

1212212112021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134690234675 (or 134690234672 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 1212212112021 its reverse (1202112122121), we get a palindrome (2414324234142).

The spelling of 1212212112021 in words is "one trillion, two hundred twelve billion, two hundred twelve million, one hundred twelve thousand, twenty-one".