20729089391 has 2 divisors, whose sum is σ = 20729089392. Its totient is φ = 20729089390.

The previous prime is 20729089363. The next prime is 20729089429. The reversal of 20729089391 is 19398092702.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20729089391 - 2⁶ = 20729089327 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20729089361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10364544695 + 10364544696.

It is an arithmetic number, because the mean of its divisors is an integer number (10364544696).

Almost surely, 2^20729089391 is an apocalyptic number.

20729089391 is a deficient number, since it is larger than the sum of its proper divisors (1).

20729089391 is an equidigital number, since it uses as much as digits as its factorization.

20729089391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 489888, while the sum is 50.

The spelling of 20729089391 in words is "twenty billion, seven hundred twenty-nine million, eighty-nine thousand, three hundred ninety-one".