1212101021 has 2 divisors, whose sum is σ = 1212101022. Its totient is φ = 1212101020.

The previous prime is 1212101017. The next prime is 1212101027. The reversal of 1212101021 is 1201012121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1184116921 + 27984100 = 34411^2 + 5290^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212101021 - 2² = 1212101017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1212100993 and 1212101011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1212101027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606050510 + 606050511.

It is an arithmetic number, because the mean of its divisors is an integer number (606050511).

Almost surely, 2^1212101021 is an apocalyptic number.

It is an amenable number.

1212101021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212101021 is an equidigital number, since it uses as much as digits as its factorization.

1212101021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 1212101021 is about 34815.2412170302. The cubic root of 1212101021 is about 1066.2186439545.

Adding to 1212101021 its reverse (1201012121), we get a palindrome (2413113142).

Subtracting from 1212101021 its reverse (1201012121), we obtain a square (11088900 = 3330²).

The spelling of 1212101021 in words is "one billion, two hundred twelve million, one hundred one thousand, twenty-one".