1212200222021 has 4 divisors (see below), whose sum is σ = 1283506117452. Its totient is φ = 1140894326592.

The previous prime is 1212200221963. The next prime is 1212200222029. The reversal of 1212200222021 is 1202220022121.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 992952460900 + 219247761121 = 996470^2 + 468239^2 .

It is not a de Polignac number, because 1212200222021 - 2³⁰ = 1211126480197 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 71305895413 = 1212200222021 / (1 + 2 + 1 + 2 + 2 + 0 + 0 + 2 + 2 + 2 + 0 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212200222029) 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, 35652947690 + ... + 35652947723.

It is an arithmetic number, because the mean of its divisors is an integer number (320876529363).

Almost surely, 2^{1212200222021} is an apocalyptic number.

It is an amenable number.

1212200222021 is a deficient number, since it is larger than the sum of its proper divisors (71305895431).

1212200222021 is an equidigital number, since it uses as much as digits as its factorization.

1212200222021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71305895430.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 1212200222021 its reverse (1202220022121), we get a palindrome (2414420244142).

The spelling of 1212200222021 in words is "one trillion, two hundred twelve billion, two hundred million, two hundred twenty-two thousand, twenty-one".