42512081 has 2 divisors, whose sum is σ = 42512082. Its totient is φ = 42512080.

The previous prime is 42512047. The next prime is 42512083. The reversal of 42512081 is 18021524.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42510400 + 1681 = 6520^2 + 41^2 .

It is a cyclic number.

It is not a de Polignac number, because 42512081 - 2¹⁸ = 42249937 is a prime.

It is a super-2 number, since 2×42512081² = 3614554061901122, which contains 22 as substring.

Together with 42512083, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (42512083) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21256040 + 21256041.

It is an arithmetic number, because the mean of its divisors is an integer number (21256041).

Almost surely, 2^42512081 is an apocalyptic number.

It is an amenable number.

42512081 is a deficient number, since it is larger than the sum of its proper divisors (1).

42512081 is an equidigital number, since it uses as much as digits as its factorization.

42512081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 42512081 is about 6520.1289097686. The cubic root of 42512081 is about 349.0096657723.

The spelling of 42512081 in words is "forty-two million, five hundred twelve thousand, eighty-one".