205951505 has 4 divisors (see below), whose sum is σ = 247141812. Its totient is φ = 164761200.

The previous prime is 205951463. The next prime is 205951547. The reversal of 205951505 is 505159502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 505159502 = 2 ⋅252579751.

It is an interprime number because it is at equal distance from previous prime (205951463) and next prime (205951547).

It can be written as a sum of positive squares in 2 ways, for example, as 129231424 + 76720081 = 11368^2 + 8759^2 .

It is not a de Polignac number, because 205951505 - 2¹² = 205947409 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20595146 + ... + 20595155.

It is an arithmetic number, because the mean of its divisors is an integer number (61785453).

Almost surely, 2^205951505 is an apocalyptic number.

It is an amenable number.

205951505 is a deficient number, since it is larger than the sum of its proper divisors (41190307).

205951505 is an equidigital number, since it uses as much as digits as its factorization.

205951505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41190306.

The product of its (nonzero) digits is 11250, while the sum is 32.

The square root of 205951505 is about 14351.0105915925. The cubic root of 205951505 is about 590.5477102935.

The spelling of 205951505 in words is "two hundred five million, nine hundred fifty-one thousand, five hundred five".