20910489609 has 4 divisors (see below), whose sum is σ = 27880652816. Its totient is φ = 13940326404.

The previous prime is 20910489601. The next prime is 20910489623. The reversal of 20910489609 is 90698401902.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 20910489609 - 2³ = 20910489601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20910489601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3485081599 + ... + 3485081604.

It is an arithmetic number, because the mean of its divisors is an integer number (6970163204).

Almost surely, 2^20910489609 is an apocalyptic number.

It is an amenable number.

20910489609 is a deficient number, since it is larger than the sum of its proper divisors (6970163207).

20910489609 is an equidigital number, since it uses as much as digits as its factorization.

20910489609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6970163206.

The product of its (nonzero) digits is 279936, while the sum is 48.

The spelling of 20910489609 in words is "twenty billion, nine hundred ten million, four hundred eighty-nine thousand, six hundred nine".