20042340991 has 2 divisors, whose sum is σ = 20042340992. Its totient is φ = 20042340990.

The previous prime is 20042340953. The next prime is 20042341021. The reversal of 20042340991 is 19904324002.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20042340991 - 2²⁵ = 20008786559 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20042344991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10021170495 + 10021170496.

It is an arithmetic number, because the mean of its divisors is an integer number (10021170496).

Almost surely, 2^20042340991 is an apocalyptic number.

20042340991 is a deficient number, since it is larger than the sum of its proper divisors (1).

20042340991 is an equidigital number, since it uses as much as digits as its factorization.

20042340991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 34.

Adding to 20042340991 its reverse (19904324002), we get a palindrome (39946664993).

The spelling of 20042340991 in words is "twenty billion, forty-two million, three hundred forty thousand, nine hundred ninety-one".