1021121210221 has 16 divisors (see below), whose sum is σ = 1174678661376. Its totient is φ = 869486881536.

The previous prime is 1021121210203. The next prime is 1021121210251. The reversal of 1021121210221 is 1220121211201.

It is not a de Polignac number, because 1021121210221 - 2¹⁷ = 1021121079149 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1021121210195 and 1021121210204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021121210251) 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, 5197440 + ... + 5390326.

It is an arithmetic number, because the mean of its divisors is an integer number (73417416336).

Almost surely, 2^{1021121210221} is an apocalyptic number.

It is an amenable number.

1021121210221 is a deficient number, since it is larger than the sum of its proper divisors (153557451155).

1021121210221 is a wasteful number, since it uses less digits than its factorization.

1021121210221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197868.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1021121210221 its reverse (1220121211201), we get a palindrome (2241242421422).

The spelling of 1021121210221 in words is "one trillion, twenty-one billion, one hundred twenty-one million, two hundred ten thousand, two hundred twenty-one".