51505661607 has 8 divisors (see below), whose sum is σ = 68676078576. Its totient is φ = 34336176192.

The previous prime is 51505661591. The next prime is 51505661621. The reversal of 51505661607 is 70616650515.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51505661607 - 2⁴ = 51505661591 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51505661677) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 91638 + ... + 333779.

It is an arithmetic number, because the mean of its divisors is an integer number (8584509822).

Almost surely, 2^51505661607 is an apocalyptic number.

51505661607 is a deficient number, since it is larger than the sum of its proper divisors (17170416969).

51505661607 is a wasteful number, since it uses less digits than its factorization.

51505661607 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 465777.

The product of its (nonzero) digits is 189000, while the sum is 42.

The spelling of 51505661607 in words is "fifty-one billion, five hundred five million, six hundred sixty-one thousand, six hundred seven".