1012020201821 has 2 divisors, whose sum is σ = 1012020201822. Its totient is φ = 1012020201820.

The previous prime is 1012020201811. The next prime is 1012020201823. The reversal of 1012020201821 is 1281020202101.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1001322436921 + 10697764900 = 1000661^2 + 103430^2 .

It is a cyclic number.

It is not a de Polignac number, because 1012020201821 - 2¹⁰ = 1012020200797 is a prime.

Together with 1012020201823, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1012020201793 and 1012020201802.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1012020201823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 506010100910 + 506010100911.

It is an arithmetic number, because the mean of its divisors is an integer number (506010100911).

Almost surely, 2^{1012020201821} is an apocalyptic number.

It is an amenable number.

1012020201821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1012020201821 is an equidigital number, since it uses as much as digits as its factorization.

1012020201821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 1012020201821 its reverse (1281020202101), we get a palindrome (2293040403922).

The spelling of 1012020201821 in words is "one trillion, twelve billion, twenty million, two hundred one thousand, eight hundred twenty-one".