511778161 has 4 divisors (see below), whose sum is σ = 512260672. Its totient is φ = 511295652.

The previous prime is 511778147. The next prime is 511778203. The reversal of 511778161 is 161877115.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 511778161 - 2¹¹ = 511776113 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 511778161.

It is not an unprimeable number, because it can be changed into a prime (511778261) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 239661 + ... + 241786.

It is an arithmetic number, because the mean of its divisors is an integer number (128065168).

Almost surely, 2^511778161 is an apocalyptic number.

It is an amenable number.

511778161 is a deficient number, since it is larger than the sum of its proper divisors (482511).

511778161 is a wasteful number, since it uses less digits than its factorization.

511778161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 482510.

The product of its digits is 11760, while the sum is 37.

The square root of 511778161 is about 22622.5144712077. The cubic root of 511778161 is about 799.8844421630.

The spelling of 511778161 in words is "five hundred eleven million, seven hundred seventy-eight thousand, one hundred sixty-one".