205775397 has 20 divisors (see below), whose sum is σ = 308249920. Its totient is φ = 136801224.

The previous prime is 205775371. The next prime is 205775399. The reversal of 205775397 is 793577502.

It is a happy number.

205775397 is a `hidden beast` number, since 20 + 577 + 53 + 9 + 7 = 666.

It is not a de Polignac number, because 205775397 - 2¹⁴ = 205759013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205775399) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 27348 + ... + 34050.

It is an arithmetic number, because the mean of its divisors is an integer number (15412496).

Almost surely, 2^205775397 is an apocalyptic number.

205775397 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

205775397 is a deficient number, since it is larger than the sum of its proper divisors (102474523).

205775397 is an equidigital number, since it uses as much as digits as its factorization.

205775397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7094 (or 7085 counting only the distinct ones).

The product of its (nonzero) digits is 463050, while the sum is 45.

The square root of 205775397 is about 14344.8735442318. The cubic root of 205775397 is about 590.3793375924.

The spelling of 205775397 in words is "two hundred five million, seven hundred seventy-five thousand, three hundred ninety-seven".