51520345057 has 4 divisors (see below), whose sum is σ = 51522899220. Its totient is φ = 51517790896.

The previous prime is 51520345039. The next prime is 51520345111. The reversal of 51520345057 is 75054302515.

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 34159910976 + 17360434081 = 184824^2 + 131759^2 .

It is a cyclic number.

It is not a de Polignac number, because 51520345057 - 2⁷ = 51520344929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51520345757) 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, 1246582 + ... + 1287247.

It is an arithmetic number, because the mean of its divisors is an integer number (12880724805).

Almost surely, 2^51520345057 is an apocalyptic number.

It is an amenable number.

51520345057 is a deficient number, since it is larger than the sum of its proper divisors (2554163).

51520345057 is a wasteful number, since it uses less digits than its factorization.

51520345057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2554162.

The product of its (nonzero) digits is 105000, while the sum is 37.

The spelling of 51520345057 in words is "fifty-one billion, five hundred twenty million, three hundred forty-five thousand, fifty-seven".