205291379961 has 10 divisors (see below), whose sum is σ = 306669839322. Its totient is φ = 136860919920.

The previous prime is 205291379921. The next prime is 205291379971. The reversal of 205291379961 is 169973192502.

205291379961 is a `hidden beast` number, since 20 + 529 + 1 + 3 + 7 + 9 + 96 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 194012939961 + 11278440000 = 440469^2 + 106200^2 .

It is not a de Polignac number, because 205291379961 - 2¹⁸ = 205291117817 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 205291379898 and 205291379907.

It is not an unprimeable number, because it can be changed into a prime (205291379921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 1267230660 + ... + 1267230821.

Almost surely, 2^205291379961 is an apocalyptic number.

It is an amenable number.

205291379961 is a deficient number, since it is larger than the sum of its proper divisors (101378459361).

205291379961 is an equidigital number, since it uses as much as digits as its factorization.

205291379961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2534461493 (or 2534461484 counting only the distinct ones).

The product of its (nonzero) digits is 1837080, while the sum is 54.

The spelling of 205291379961 in words is "two hundred five billion, two hundred ninety-one million, three hundred seventy-nine thousand, nine hundred sixty-one".