51521115131 has 4 divisors (see below), whose sum is σ = 51521593512. Its totient is φ = 51520636752.

The previous prime is 51521115071. The next prime is 51521115137. The reversal of 51521115131 is 13151112515.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 51521115131 - 2¹⁴ = 51521098747 is a prime.

It is a super-2 number, since 2×51521115131² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51521115131.

It is not an unprimeable number, because it can be changed into a prime (51521115137) 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, 6440 + ... + 321066.

It is an arithmetic number, because the mean of its divisors is an integer number (12880398378).

Almost surely, 2^51521115131 is an apocalyptic number.

51521115131 is a deficient number, since it is larger than the sum of its proper divisors (478381).

51521115131 is a wasteful number, since it uses less digits than its factorization.

51521115131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 478380.

The product of its digits is 750, while the sum is 26.

Adding to 51521115131 its reverse (13151112515), we get a palindrome (64672227646).

The spelling of 51521115131 in words is "fifty-one billion, five hundred twenty-one million, one hundred fifteen thousand, one hundred thirty-one".