780505 has 16 divisors (see below), whose sum is σ = 1067904. Its totient is φ = 542080.

The previous prime is 780499. The next prime is 780523. The reversal of 780505 is 505087.

It is not a de Polignac number, because 780505 - 2⁹ = 779993 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 780505.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 957 + ... + 1573.

It is an arithmetic number, because the mean of its divisors is an integer number (66744).

2⁷⁸⁰⁵⁰⁵ is an apocalyptic number.

It is an amenable number.

780505 is a deficient number, since it is larger than the sum of its proper divisors (287399).

780505 is a wasteful number, since it uses less digits than its factorization.

780505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 656.

The product of its (nonzero) digits is 1400, while the sum is 25.

The square root of 780505 is about 883.4619403234. The cubic root of 780505 is about 92.0715023850.

The spelling of 780505 in words is "seven hundred eighty thousand, five hundred five".