213121021097 has 2 divisors, whose sum is σ = 213121021098. Its totient is φ = 213121021096.

The previous prime is 213121021049. The next prime is 213121021111. The reversal of 213121021097 is 790120121312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 200479167001 + 12641854096 = 447749^2 + 112436^2 .

It is a cyclic number.

It is not a de Polignac number, because 213121021097 - 2⁸ = 213121020841 is a prime.

It is not a weakly prime, because it can be changed into another prime (213121021037) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106560510548 + 106560510549.

It is an arithmetic number, because the mean of its divisors is an integer number (106560510549).

Almost surely, 2^213121021097 is an apocalyptic number.

It is an amenable number.

213121021097 is a deficient number, since it is larger than the sum of its proper divisors (1).

213121021097 is an equidigital number, since it uses as much as digits as its factorization.

213121021097 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1512, while the sum is 29.

The spelling of 213121021097 in words is "two hundred thirteen billion, one hundred twenty-one million, twenty-one thousand, ninety-seven".