206101777381 has 2 divisors, whose sum is σ = 206101777382. Its totient is φ = 206101777380.

The previous prime is 206101777363. The next prime is 206101777397. The reversal of 206101777381 is 183777101602.

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., 195931054881 + 10170722500 = 442641^2 + 100850^2 .

It is a cyclic number.

It is not a de Polignac number, because 206101777381 - 2¹¹ = 206101775333 is a prime.

It is a super-2 number, since 2×206101777381² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206101775381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103050888690 + 103050888691.

It is an arithmetic number, because the mean of its divisors is an integer number (103050888691).

Almost surely, 2^206101777381 is an apocalyptic number.

It is an amenable number.

206101777381 is a deficient number, since it is larger than the sum of its proper divisors (1).

206101777381 is an equidigital number, since it uses as much as digits as its factorization.

206101777381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 98784, while the sum is 43.

Adding to 206101777381 its reverse (183777101602), we get a palindrome (389878878983).

The spelling of 206101777381 in words is "two hundred six billion, one hundred one million, seven hundred seventy-seven thousand, three hundred eighty-one".