20840903287 has 2 divisors, whose sum is σ = 20840903288. Its totient is φ = 20840903286.

The previous prime is 20840903269. The next prime is 20840903297. The reversal of 20840903287 is 78230904802.

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-20840903287 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20840903297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10420451643 + 10420451644.

It is an arithmetic number, because the mean of its divisors is an integer number (10420451644).

Almost surely, 2^20840903287 is an apocalyptic number.

20840903287 is a deficient number, since it is larger than the sum of its proper divisors (1).

20840903287 is an equidigital number, since it uses as much as digits as its factorization.

20840903287 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 193536, while the sum is 43.

The spelling of 20840903287 in words is "twenty billion, eight hundred forty million, nine hundred three thousand, two hundred eighty-seven".