1021221111021 has 16 divisors (see below), whose sum is σ = 1363230283584. Its totient is φ = 680013247104.

The previous prime is 1021221111019. The next prime is 1021221111067. The reversal of 1021221111021 is 1201111221201.

It is a happy number.

It is not a de Polignac number, because 1021221111021 - 2¹ = 1021221111019 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021221111011) 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, 19334370 + ... + 19387116.

It is an arithmetic number, because the mean of its divisors is an integer number (85201892724).

Almost surely, 2^{1021221111021} is an apocalyptic number.

It is an amenable number.

1021221111021 is a deficient number, since it is larger than the sum of its proper divisors (342009172563).

1021221111021 is an equidigital number, since it uses as much as digits as its factorization.

1021221111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60220.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1021221111021 its reverse (1201111221201), we get a palindrome (2222332332222).

The spelling of 1021221111021 in words is "one trillion, twenty-one billion, two hundred twenty-one million, one hundred eleven thousand, twenty-one".