51115635247 has 4 divisors (see below), whose sum is σ = 51118917696. Its totient is φ = 51112352800.

The previous prime is 51115635227. The next prime is 51115635287. The reversal of 51115635247 is 74253651115.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51115635247 is a prime.

It is a super-2 number, since 2×51115635247² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51115635227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1617754 + ... + 1649047.

It is an arithmetic number, because the mean of its divisors is an integer number (12779729424).

Almost surely, 2^51115635247 is an apocalyptic number.

51115635247 is a deficient number, since it is larger than the sum of its proper divisors (3282449).

51115635247 is a wasteful number, since it uses less digits than its factorization.

51115635247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3282448.

The product of its digits is 126000, while the sum is 40.

The spelling of 51115635247 in words is "fifty-one billion, one hundred fifteen million, six hundred thirty-five thousand, two hundred forty-seven".