20729089397 has 4 divisors (see below), whose sum is σ = 20912532780. Its totient is φ = 20545646016.

The previous prime is 20729089391. The next prime is 20729089429. The reversal of 20729089397 is 79398092702.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1297008196 + 19432081201 = 36014^2 + 139399^2 .

It is a cyclic number.

It is not a de Polignac number, because 20729089397 - 2¹⁸ = 20728827253 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20729089391) 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 in 3 ways as a sum of consecutive naturals, for example, 91721522 + ... + 91721747.

It is an arithmetic number, because the mean of its divisors is an integer number (5228133195).

Almost surely, 2^20729089397 is an apocalyptic number.

It is an amenable number.

20729089397 is a deficient number, since it is larger than the sum of its proper divisors (183443383).

20729089397 is a wasteful number, since it uses less digits than its factorization.

20729089397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183443382.

The product of its (nonzero) digits is 3429216, while the sum is 56.

The spelling of 20729089397 in words is "twenty billion, seven hundred twenty-nine million, eighty-nine thousand, three hundred ninety-seven".