511656605551 has 24 divisors (see below), whose sum is σ = 666517153920. Its totient is φ = 383520492576.

The previous prime is 511656605531. The next prime is 511656605567. The reversal of 511656605551 is 155506656115.

It is a happy number.

It is not a de Polignac number, because 511656605551 - 2⁷ = 511656605423 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (511656605531) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11359305 + ... + 11404258.

It is an arithmetic number, because the mean of its divisors is an integer number (27771548080).

Almost surely, 2^511656605551 is an apocalyptic number.

511656605551 is a deficient number, since it is larger than the sum of its proper divisors (154860548369).

511656605551 is a wasteful number, since it uses less digits than its factorization.

511656605551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22763615 (or 22763602 counting only the distinct ones).

The product of its (nonzero) digits is 675000, while the sum is 46.

The spelling of 511656605551 in words is "five hundred eleven billion, six hundred fifty-six million, six hundred five thousand, five hundred fifty-one".