51725205509 has 2 divisors, whose sum is σ = 51725205510. Its totient is φ = 51725205508.

The previous prime is 51725205473. The next prime is 51725205547. The reversal of 51725205509 is 90550252715.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49501800100 + 2223405409 = 222490^2 + 47153^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51725205509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51725205409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25862602754 + 25862602755.

It is an arithmetic number, because the mean of its divisors is an integer number (25862602755).

Almost surely, 2^51725205509 is an apocalyptic number.

It is an amenable number.

51725205509 is a deficient number, since it is larger than the sum of its proper divisors (1).

51725205509 is an equidigital number, since it uses as much as digits as its factorization.

51725205509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 157500, while the sum is 41.

The spelling of 51725205509 in words is "fifty-one billion, seven hundred twenty-five million, two hundred five thousand, five hundred nine".