212769539681 has 2 divisors, whose sum is σ = 212769539682. Its totient is φ = 212769539680.

The previous prime is 212769539669. The next prime is 212769539683. The reversal of 212769539681 is 186935967212.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 134805731281 + 77963808400 = 367159^2 + 279220^2 .

It is a cyclic number.

It is not a de Polignac number, because 212769539681 - 2⁶ = 212769539617 is a prime.

It is a super-4 number, since 4×212769539681⁴ (a number of 46 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

Together with 212769539683, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 212769539681.

It is not a weakly prime, because it can be changed into another prime (212769539683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106384769840 + 106384769841.

It is an arithmetic number, because the mean of its divisors is an integer number (106384769841).

Almost surely, 2^212769539681 is an apocalyptic number.

It is an amenable number.

212769539681 is a deficient number, since it is larger than the sum of its proper divisors (1).

212769539681 is an equidigital number, since it uses as much as digits as its factorization.

212769539681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9797760, while the sum is 59.

The spelling of 212769539681 in words is "two hundred twelve billion, seven hundred sixty-nine million, five hundred thirty-nine thousand, six hundred eighty-one".