1212122020021 has 4 divisors (see below), whose sum is σ = 1322314930944. Its totient is φ = 1101929109100.

The previous prime is 1212122019961. The next prime is 1212122020037. The reversal of 1212122020021 is 1200202212121.

It is a happy number.

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 not a de Polignac number, because 1212122020021 - 2⁷ = 1212122019893 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1212122019977 and 1212122020004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212122020621) 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, 55096455445 + ... + 55096455466.

It is an arithmetic number, because the mean of its divisors is an integer number (330578732736).

Almost surely, 2^{1212122020021} is an apocalyptic number.

1212122020021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1212122020021 is a deficient number, since it is larger than the sum of its proper divisors (110192910923).

1212122020021 is a wasteful number, since it uses less digits than its factorization.

1212122020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110192910922.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 1212122020021 its reverse (1200202212121), we get a palindrome (2412324232142).

The spelling of 1212122020021 in words is "one trillion, two hundred twelve billion, one hundred twenty-two million, twenty thousand, twenty-one".