205151405 has 4 divisors (see below), whose sum is σ = 246181692. Its totient is φ = 164121120.

The previous prime is 205151399. The next prime is 205151431. The reversal of 205151405 is 504151502.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 107101801 + 98049604 = 10349^2 + 9902^2 .

It is a de Polignac number, because none of the positive numbers 2^k-205151405 is a prime.

It is a Duffinian number.

It is a congruent 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, 20515136 + ... + 20515145.

It is an arithmetic number, because the mean of its divisors is an integer number (61545423).

Almost surely, 2^205151405 is an apocalyptic number.

It is an amenable number.

205151405 is a deficient number, since it is larger than the sum of its proper divisors (41030287).

205151405 is an equidigital number, since it uses as much as digits as its factorization.

205151405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41030286.

The product of its (nonzero) digits is 1000, while the sum is 23.

The square root of 205151405 is about 14323.1073793364. The cubic root of 205151405 is about 589.7819791983.

The spelling of 205151405 in words is "two hundred five million, one hundred fifty-one thousand, four hundred five".