51005555605 has 4 divisors (see below), whose sum is σ = 61206666732. Its totient is φ = 40804444480.

The previous prime is 51005555567. The next prime is 51005555621. The reversal of 51005555605 is 50655550015.

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

It can be written as a sum of positive squares in 2 ways, for example, as 24221941956 + 26783613649 = 155634^2 + 163657^2 .

It is not a de Polignac number, because 51005555605 - 2⁷ = 51005555477 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, 5100555556 + ... + 5100555565.

It is an arithmetic number, because the mean of its divisors is an integer number (15301666683).

Almost surely, 2^51005555605 is an apocalyptic number.

It is an amenable number.

51005555605 is a deficient number, since it is larger than the sum of its proper divisors (10201111127).

51005555605 is a wasteful number, since it uses less digits than its factorization.

51005555605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10201111126.

The product of its (nonzero) digits is 93750, while the sum is 37.

The spelling of 51005555605 in words is "fifty-one billion, five million, five hundred fifty-five thousand, six hundred five".