1021022001221 has 2 divisors, whose sum is σ = 1021022001222. Its totient is φ = 1021022001220.

The previous prime is 1021022001163. The next prime is 1021022001239. The reversal of 1021022001221 is 1221002201201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 590882778721 + 430139222500 = 768689^2 + 655850^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021022001221 - 2³⁰ = 1019948259397 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1021022001196 and 1021022001205.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021022001271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510511000610 + 510511000611.

It is an arithmetic number, because the mean of its divisors is an integer number (510511000611).

Almost surely, 2^{1021022001221} is an apocalyptic number.

It is an amenable number.

1021022001221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021022001221 is an equidigital number, since it uses as much as digits as its factorization.

1021022001221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 1021022001221 its reverse (1221002201201), we get a palindrome (2242024202422).

The spelling of 1021022001221 in words is "one trillion, twenty-one billion, twenty-two million, one thousand, two hundred twenty-one".