1220021212121 has 16 divisors (see below), whose sum is σ = 1290295847808. Its totient is φ = 1151272953600.

The previous prime is 1220021212097. The next prime is 1220021212129. The reversal of 1220021212121 is 1212121200221.

It is a cyclic number.

It is not a de Polignac number, because 1220021212121 - 2¹⁸ = 1220020949977 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1220021212121.

It is not an unprimeable number, because it can be changed into a prime (1220021212129) 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, 435410 + ... + 1621611.

It is an arithmetic number, because the mean of its divisors is an integer number (80643490488).

Almost surely, 2^{1220021212121} is an apocalyptic number.

It is an amenable number.

1220021212121 is a deficient number, since it is larger than the sum of its proper divisors (70274635687).

1220021212121 is a wasteful number, since it uses less digits than its factorization.

1220021212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2057392.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 1220021212121 its reverse (1212121200221), we get a palindrome (2432142412342).

The spelling of 1220021212121 in words is "one trillion, two hundred twenty billion, twenty-one million, two hundred twelve thousand, one hundred twenty-one".