505581905 has 4 divisors (see below), whose sum is σ = 606698292. Its totient is φ = 404465520.

The previous prime is 505581877. The next prime is 505581913. The reversal of 505581905 is 509185505.

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 92313664 + 413268241 = 9608^2 + 20329^2 .

It is not a de Polignac number, because 505581905 - 2¹⁸ = 505319761 is a prime.

It is a super-2 number, since 2×505581905² = 511226125326858050, which contains 22 as substring.

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, 50558186 + ... + 50558195.

It is an arithmetic number, because the mean of its divisors is an integer number (151674573).

Almost surely, 2^505581905 is an apocalyptic number.

It is an amenable number.

505581905 is a deficient number, since it is larger than the sum of its proper divisors (101116387).

505581905 is a wasteful number, since it uses less digits than its factorization.

505581905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101116386.

The product of its (nonzero) digits is 45000, while the sum is 38.

The square root of 505581905 is about 22485.1485429828. The cubic root of 505581905 is about 796.6431765588.

The spelling of 505581905 in words is "five hundred five million, five hundred eighty-one thousand, nine hundred five".