205381961 has 4 divisors (see below), whose sum is σ = 205446672. Its totient is φ = 205317252.

The previous prime is 205381951. The next prime is 205381991. The reversal of 205381961 is 169183502.

205381961 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 169183502 = 2 ⋅84591751.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205381961 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (205381901) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27335 + ... + 34028.

It is an arithmetic number, because the mean of its divisors is an integer number (51361668).

Almost surely, 2^205381961 is an apocalyptic number.

It is an amenable number.

205381961 is a deficient number, since it is larger than the sum of its proper divisors (64711).

205381961 is an equidigital number, since it uses as much as digits as its factorization.

205381961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64710.

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 205381961 is about 14331.1535125404. The cubic root of 205381961 is about 590.0028353785.

The spelling of 205381961 in words is "two hundred five million, three hundred eighty-one thousand, nine hundred sixty-one".