212120995817 has 2 divisors, whose sum is σ = 212120995818. Its totient is φ = 212120995816.

The previous prime is 212120995811. The next prime is 212120995831. The reversal of 212120995817 is 718599021212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 182960652121 + 29160343696 = 427739^2 + 170764^2 .

It is a cyclic number.

It is not a de Polignac number, because 212120995817 - 2¹² = 212120991721 is a prime.

It is a super-3 number, since 3×212120995817³ (a number of 35 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (212120995811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106060497908 + 106060497909.

It is an arithmetic number, because the mean of its divisors is an integer number (106060497909).

Almost surely, 2^212120995817 is an apocalyptic number.

It is an amenable number.

212120995817 is a deficient number, since it is larger than the sum of its proper divisors (1).

212120995817 is an equidigital number, since it uses as much as digits as its factorization.

212120995817 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 181440, while the sum is 47.

The spelling of 212120995817 in words is "two hundred twelve billion, one hundred twenty million, nine hundred ninety-five thousand, eight hundred seventeen".