205921954700381 has 2 divisors, whose sum is σ = 205921954700382. Its totient is φ = 205921954700380.

The previous prime is 205921954700353. The next prime is 205921954700387. The reversal of 205921954700381 is 183007459129502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 175198314062500 + 30723640637881 = 13236250^2 + 5542891^2 .

It is a cyclic number.

It is not a de Polignac number, because 205921954700381 - 2³⁰ = 205920880958557 is a prime.

It is a super-2 number, since 2×205921954700381² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205921954700387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102960977350190 + 102960977350191.

It is an arithmetic number, because the mean of its divisors is an integer number (102960977350191).

Almost surely, 2^{205921954700381} is an apocalyptic number.

It is an amenable number.

205921954700381 is a deficient number, since it is larger than the sum of its proper divisors (1).

205921954700381 is an equidigital number, since it uses as much as digits as its factorization.

205921954700381 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5443200, while the sum is 56.

The spelling of 205921954700381 in words is "two hundred five trillion, nine hundred twenty-one billion, nine hundred fifty-four million, seven hundred thousand, three hundred eighty-one".