20115240643 has 2 divisors, whose sum is σ = 20115240644. Its totient is φ = 20115240642.

The previous prime is 20115240641. The next prime is 20115240653. The reversal of 20115240643 is 34604251102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20115240643 - 2¹ = 20115240641 is a prime.

It is a super-2 number, since 2×20115240643² (a number of 21 digits) contains 22 as substring.

Together with 20115240641, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20115240641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10057620321 + 10057620322.

It is an arithmetic number, because the mean of its divisors is an integer number (10057620322).

Almost surely, 2^20115240643 is an apocalyptic number.

20115240643 is a deficient number, since it is larger than the sum of its proper divisors (1).

20115240643 is an equidigital number, since it uses as much as digits as its factorization.

20115240643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5760, while the sum is 28.

Adding to 20115240643 its reverse (34604251102), we get a palindrome (54719491745).

The spelling of 20115240643 in words is "twenty billion, one hundred fifteen million, two hundred forty thousand, six hundred forty-three".