42565121329 has 2 divisors, whose sum is σ = 42565121330. Its totient is φ = 42565121328.

The previous prime is 42565121311. The next prime is 42565121353. The reversal of 42565121329 is 92312156524.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38488554225 + 4076567104 = 196185^2 + 63848^2 .

It is a cyclic number.

It is not a de Polignac number, because 42565121329 - 2¹⁷ = 42564990257 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 42565121291 and 42565121300.

It is not a weakly prime, because it can be changed into another prime (42565121359) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21282560664 + 21282560665.

It is an arithmetic number, because the mean of its divisors is an integer number (21282560665).

Almost surely, 2^42565121329 is an apocalyptic number.

It is an amenable number.

42565121329 is a deficient number, since it is larger than the sum of its proper divisors (1).

42565121329 is an equidigital number, since it uses as much as digits as its factorization.

42565121329 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129600, while the sum is 40.

The spelling of 42565121329 in words is "forty-two billion, five hundred sixty-five million, one hundred twenty-one thousand, three hundred twenty-nine".