51023535209 has 2 divisors, whose sum is σ = 51023535210. Its totient is φ = 51023535208.

The previous prime is 51023535169. The next prime is 51023535253. The reversal of 51023535209 is 90253532015.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49030359184 + 1993176025 = 221428^2 + 44645^2 .

It is a cyclic number.

It is not a de Polignac number, because 51023535209 - 2²⁰ = 51022486633 is a prime.

It is a super-2 number, since 2×51023535209² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51023535509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25511767604 + 25511767605.

It is an arithmetic number, because the mean of its divisors is an integer number (25511767605).

Almost surely, 2^51023535209 is an apocalyptic number.

It is an amenable number.

51023535209 is a deficient number, since it is larger than the sum of its proper divisors (1).

51023535209 is an equidigital number, since it uses as much as digits as its factorization.

51023535209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40500, while the sum is 35.

The spelling of 51023535209 in words is "fifty-one billion, twenty-three million, five hundred thirty-five thousand, two hundred nine".