1021211222221 has 16 divisors (see below), whose sum is σ = 1070131765248. Its totient is φ = 973318777200.

The previous prime is 1021211222219. The next prime is 1021211222243. The reversal of 1021211222221 is 1222221121201.

It is a cyclic number.

It is not a de Polignac number, because 1021211222221 - 2¹ = 1021211222219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021211222821) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1839376 + ... + 2329318.

It is an arithmetic number, because the mean of its divisors is an integer number (66883235328).

Almost surely, 2^{1021211222221} is an apocalyptic number.

It is an amenable number.

1021211222221 is a deficient number, since it is larger than the sum of its proper divisors (48920543027).

1021211222221 is an equidigital number, since it uses as much as digits as its factorization.

1021211222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 490992.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 1021211222221 its reverse (1222221121201), we get a palindrome (2243432343422).

The spelling of 1021211222221 in words is "one trillion, twenty-one billion, two hundred eleven million, two hundred twenty-two thousand, two hundred twenty-one".