51505531109 has 16 divisors (see below), whose sum is σ = 52782102384. Its totient is φ = 50244364800.

The previous prime is 51505531087. The next prime is 51505531117. The reversal of 51505531109 is 90113550515.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 991620100 + 50513911009 = 31490^2 + 224753^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51505531109 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 (51505531009) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4437017 + ... + 4448609.

It is an arithmetic number, because the mean of its divisors is an integer number (3298881399).

Almost surely, 2^51505531109 is an apocalyptic number.

It is an amenable number.

51505531109 is a deficient number, since it is larger than the sum of its proper divisors (1276571275).

51505531109 is a wasteful number, since it uses less digits than its factorization.

51505531109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12248.

The product of its (nonzero) digits is 16875, while the sum is 35.

The spelling of 51505531109 in words is "fifty-one billion, five hundred five million, five hundred thirty-one thousand, one hundred nine".