51011512613 has 4 divisors (see below), whose sum is σ = 51234270540. Its totient is φ = 50788754688.

The previous prime is 51011512597. The next prime is 51011512667. The reversal of 51011512613 is 31621511015.

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 47468644129 + 3542868484 = 217873^2 + 59522^2 .

It is a cyclic number.

It is not a de Polignac number, because 51011512613 - 2⁴ = 51011512597 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51011512693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111378620 + ... + 111379077.

It is an arithmetic number, because the mean of its divisors is an integer number (12808567635).

Almost surely, 2^51011512613 is an apocalyptic number.

It is an amenable number.

51011512613 is a deficient number, since it is larger than the sum of its proper divisors (222757927).

51011512613 is a wasteful number, since it uses less digits than its factorization.

51011512613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222757926.

The product of its (nonzero) digits is 900, while the sum is 26.

The spelling of 51011512613 in words is "fifty-one billion, eleven million, five hundred twelve thousand, six hundred thirteen".