511616511655 has 4 divisors (see below), whose sum is σ = 613939813992. Its totient is φ = 409293209320.

The previous prime is 511616511647. The next prime is 511616511661. The reversal of 511616511655 is 556115616115.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 511616511655 - 2³ = 511616511647 is a prime.

It is a Duffinian number.

It is a congruent 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, 51161651161 + ... + 51161651170.

It is an arithmetic number, because the mean of its divisors is an integer number (153484953498).

Almost surely, 2^511616511655 is an apocalyptic number.

511616511655 is a deficient number, since it is larger than the sum of its proper divisors (102323302337).

511616511655 is a wasteful number, since it uses less digits than its factorization.

511616511655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102323302336.

The product of its digits is 135000, while the sum is 43.

The spelling of 511616511655 in words is "five hundred eleven billion, six hundred sixteen million, five hundred eleven thousand, six hundred fifty-five".