121211021021 has 2 divisors, whose sum is σ = 121211021022. Its totient is φ = 121211021020.

The previous prime is 121211021011. The next prime is 121211021027. The reversal of 121211021021 is 120120112121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 120773625625 + 437395396 = 347525^2 + 20914^2 .

It is an emirp because it is prime and its reverse (120120112121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121211021021 - 2¹⁴ = 121211004637 is a prime.

It is a super-2 number, since 2×121211021021² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 121211020987 and 121211021005.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121211021027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60605510510 + 60605510511.

It is an arithmetic number, because the mean of its divisors is an integer number (60605510511).

Almost surely, 2^121211021021 is an apocalyptic number.

It is an amenable number.

121211021021 is a deficient number, since it is larger than the sum of its proper divisors (1).

121211021021 is an equidigital number, since it uses as much as digits as its factorization.

121211021021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 121211021021 its reverse (120120112121), we get a palindrome (241331133142).

The spelling of 121211021021 in words is "one hundred twenty-one billion, two hundred eleven million, twenty-one thousand, twenty-one".