20840657371 has 2 divisors, whose sum is σ = 20840657372. Its totient is φ = 20840657370.

The previous prime is 20840657363. The next prime is 20840657377. The reversal of 20840657371 is 17375604802.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20840657371 - 2³ = 20840657363 is a prime.

It is not a weakly prime, because it can be changed into another prime (20840657377) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10420328685 + 10420328686.

It is an arithmetic number, because the mean of its divisors is an integer number (10420328686).

Almost surely, 2^20840657371 is an apocalyptic number.

20840657371 is a deficient number, since it is larger than the sum of its proper divisors (1).

20840657371 is an equidigital number, since it uses as much as digits as its factorization.

20840657371 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 282240, while the sum is 43.

The spelling of 20840657371 in words is "twenty billion, eight hundred forty million, six hundred fifty-seven thousand, three hundred seventy-one".