206780505 has 16 divisors (see below), whose sum is σ = 331730880. Its totient is φ = 109988928.

The previous prime is 206780501. The next prime is 206780533. The reversal of 206780505 is 505087602.

It is a happy number.

It is not a de Polignac number, because 206780505 - 2² = 206780501 is a prime.

It is not an unprimeable number, because it can be changed into a prime (206780501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12502 + ... + 23871.

It is an arithmetic number, because the mean of its divisors is an integer number (20733180).

Almost surely, 2^206780505 is an apocalyptic number.

It is an amenable number.

206780505 is a deficient number, since it is larger than the sum of its proper divisors (124950375).

206780505 is a wasteful number, since it uses less digits than its factorization.

206780505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36760.

The product of its (nonzero) digits is 16800, while the sum is 33.

The square root of 206780505 is about 14379.8645682079. The cubic root of 206780505 is about 591.3390108948.

The spelling of 206780505 in words is "two hundred six million, seven hundred eighty thousand, five hundred five".