42020335847891 has 2 divisors, whose sum is σ = 42020335847892. Its totient is φ = 42020335847890.

The previous prime is 42020335847801. The next prime is 42020335847899. The reversal of 42020335847891 is 19874853302024.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 42020335847891 - 2⁴² = 37622289336787 is a prime.

It is not a weakly prime, because it can be changed into another prime (42020335847899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21010167923945 + 21010167923946.

It is an arithmetic number, because the mean of its divisors is an integer number (21010167923946).

Almost surely, 2^{42020335847891} is an apocalyptic number.

42020335847891 is a deficient number, since it is larger than the sum of its proper divisors (1).

42020335847891 is an equidigital number, since it uses as much as digits as its factorization.

42020335847891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11612160, while the sum is 56.

The spelling of 42020335847891 in words is "forty-two trillion, twenty billion, three hundred thirty-five million, eight hundred forty-seven thousand, eight hundred ninety-one".