42565031255221 has 2 divisors, whose sum is σ = 42565031255222. Its totient is φ = 42565031255220.

The previous prime is 42565031255207. The next prime is 42565031255237. The reversal of 42565031255221 is 12255213056524.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21428668650321 + 21136362604900 = 4629111^2 + 4597430^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42565031255221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42565031255821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21282515627610 + 21282515627611.

It is an arithmetic number, because the mean of its divisors is an integer number (21282515627611).

Almost surely, 2^{42565031255221} is an apocalyptic number.

It is an amenable number.

42565031255221 is a deficient number, since it is larger than the sum of its proper divisors (1).

42565031255221 is an equidigital number, since it uses as much as digits as its factorization.

42565031255221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720000, while the sum is 43.

The spelling of 42565031255221 in words is "forty-two trillion, five hundred sixty-five billion, thirty-one million, two hundred fifty-five thousand, two hundred twenty-one".