42635891 has 2 divisors, whose sum is σ = 42635892. Its totient is φ = 42635890.

The previous prime is 42635861. The next prime is 42635893. The reversal of 42635891 is 19853624.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42635891 is a prime.

Together with 42635893, 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 (42635893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21317945 + 21317946.

It is an arithmetic number, because the mean of its divisors is an integer number (21317946).

Almost surely, 2^42635891 is an apocalyptic number.

42635891 is a deficient number, since it is larger than the sum of its proper divisors (1).

42635891 is an equidigital number, since it uses as much as digits as its factorization.

42635891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 38.

The square root of 42635891 is about 6529.6164512167. The cubic root of 42635891 is about 349.3481499949.

The spelling of 42635891 in words is "forty-two million, six hundred thirty-five thousand, eight hundred ninety-one".