1101020021 has 2 divisors, whose sum is σ = 1101020022. Its totient is φ = 1101020020.

The previous prime is 1101019991. The next prime is 1101020033. The reversal of 1101020021 is 1200201011.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 912946225 + 188073796 = 30215^2 + 13714^2 .

It is a cyclic number.

It is not a de Polignac number, because 1101020021 - 2³⁰ = 27278197 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1101019990 and 1101020008.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1101020071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 550510010 + 550510011.

It is an arithmetic number, because the mean of its divisors is an integer number (550510011).

Almost surely, 2^1101020021 is an apocalyptic number.

It is an amenable number.

1101020021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1101020021 is an equidigital number, since it uses as much as digits as its factorization.

1101020021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1101020021 is about 33181.6217355331. The cubic root of 1101020021 is about 1032.5990918503.

Adding to 1101020021 its reverse (1200201011), we get a palindrome (2301221032).

The spelling of 1101020021 in words is "one billion, one hundred one million, twenty thousand, twenty-one".