1212212020221 has 24 divisors (see below), whose sum is σ = 1798388196384. Its totient is φ = 786259599840.

The previous prime is 1212212020183. The next prime is 1212212020277. The reversal of 1212212020221 is 1220202122121.

It is a happy number.

1212212020221 is a `hidden beast` number, since 1 + 21 + 221 + 202 + 0 + 221 = 666.

It is not a de Polignac number, because 1212212020221 - 2⁷ = 1212212020093 is a prime.

It is a super-2 number, since 2×1212212020221² (a number of 25 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1212212020194 and 1212212020203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212212020291) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7341250 + ... + 7504556.

It is an arithmetic number, because the mean of its divisors is an integer number (74932841516).

Almost surely, 2^{1212212020221} is an apocalyptic number.

It is an amenable number.

1212212020221 is a deficient number, since it is larger than the sum of its proper divisors (586176176163).

1212212020221 is a wasteful number, since it uses less digits than its factorization.

1212212020221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185641 (or 185638 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 1212212020221 its reverse (1220202122121), we get a palindrome (2432414142342).

The spelling of 1212212020221 in words is "one trillion, two hundred twelve billion, two hundred twelve million, twenty thousand, two hundred twenty-one".