21031210233197 has 2 divisors, whose sum is σ = 21031210233198. Its totient is φ = 21031210233196.

The previous prime is 21031210233151. The next prime is 21031210233203. The reversal of 21031210233197 is 79133201213012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21005593910596 + 25616322601 = 4583186^2 + 160051^2 .

It is a cyclic number.

It is not a de Polignac number, because 21031210233197 - 2³⁰ = 21030136491373 is a prime.

It is a super-2 number, since 2×21031210233197² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21031210263197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515605116598 + 10515605116599.

It is an arithmetic number, because the mean of its divisors is an integer number (10515605116599).

Almost surely, 2^{21031210233197} is an apocalyptic number.

It is an amenable number.

21031210233197 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031210233197 is an equidigital number, since it uses as much as digits as its factorization.

21031210233197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13608, while the sum is 35.

The spelling of 21031210233197 in words is "twenty-one trillion, thirty-one billion, two hundred ten million, two hundred thirty-three thousand, one hundred ninety-seven".