1021111020021 has 4 divisors (see below), whose sum is σ = 1361481360032. Its totient is φ = 680740680012.

The previous prime is 1021111020011. The next prime is 1021111020029. The reversal of 1021111020021 is 1200201111201.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1021111020021 - 2¹⁹ = 1021110495733 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1021111019979 and 1021111020006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021111020029) 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, 170185170001 + ... + 170185170006.

It is an arithmetic number, because the mean of its divisors is an integer number (340370340008).

Almost surely, 2^{1021111020021} is an apocalyptic number.

It is an amenable number.

1021111020021 is a deficient number, since it is larger than the sum of its proper divisors (340370340011).

1021111020021 is an equidigital number, since it uses as much as digits as its factorization.

1021111020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340370340010.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 1021111020021 its reverse (1200201111201), we get a palindrome (2221312131222).

The spelling of 1021111020021 in words is "one trillion, twenty-one billion, one hundred eleven million, twenty thousand, twenty-one".