42135251 has 2 divisors, whose sum is σ = 42135252. Its totient is φ = 42135250.

The previous prime is 42135239. The next prime is 42135253. The reversal of 42135251 is 15253124.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 42135251 - 2⁶ = 42135187 is a prime.

Together with 42135253, 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 (42135253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21067625 + 21067626.

It is an arithmetic number, because the mean of its divisors is an integer number (21067626).

Almost surely, 2^42135251 is an apocalyptic number.

42135251 is a deficient number, since it is larger than the sum of its proper divisors (1).

42135251 is an equidigital number, since it uses as much as digits as its factorization.

42135251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1200, while the sum is 23.

The square root of 42135251 is about 6491.1671523694. The cubic root of 42135251 is about 347.9753885576.

Adding to 42135251 its reverse (15253124), we get a palindrome (57388375).

The spelling of 42135251 in words is "forty-two million, one hundred thirty-five thousand, two hundred fifty-one".