505000090 has 64 divisors (see below), whose sum is σ = 1062574848. Its totient is φ = 169228800.

The previous prime is 505000073. The next prime is 505000091. The reversal of 505000090 is 90000505.

505000090 is a nontrivial binomial coefficient, being equal to C(31781, 2).

It is not an unprimeable number, because it can be changed into a prime (505000091) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 969030 + ... + 969550.

It is an arithmetic number, because the mean of its divisors is an integer number (16602732).

Almost surely, 2^505000090 is an apocalyptic number.

505000090 is the 31780-th triangular number.

505000090 is the 10594-th centered nonagonal number.

505000090 is an abundant number, since it is smaller than the sum of its proper divisors (557574758).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

505000090 is a wasteful number, since it uses less digits than its factorization.

505000090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 823.

The product of its (nonzero) digits is 225, while the sum is 19.

The square root of 505000090 is about 22472.2070567179. The cubic root of 505000090 is about 796.3374714861.

Adding to 505000090 its reverse (90000505), we get a palindrome (595000595).

The spelling of 505000090 in words is "five hundred five million, ninety", and thus it is an aban number.