20495489705 has 4 divisors (see below), whose sum is σ = 24594587652. Its totient is φ = 16396391760.

The previous prime is 20495489701. The next prime is 20495489723. The reversal of 20495489705 is 50798459402.

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 5778888361 + 14716601344 = 76019^2 + 121312^2 .

It is not a de Polignac number, because 20495489705 - 2² = 20495489701 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20495489701) 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, 2049548966 + ... + 2049548975.

It is an arithmetic number, because the mean of its divisors is an integer number (6148646913).

Almost surely, 2^20495489705 is an apocalyptic number.

It is an amenable number.

20495489705 is a deficient number, since it is larger than the sum of its proper divisors (4099097947).

20495489705 is an equidigital number, since it uses as much as digits as its factorization.

20495489705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4099097946.

The product of its (nonzero) digits is 3628800, while the sum is 53.

The spelling of 20495489705 in words is "twenty billion, four hundred ninety-five million, four hundred eighty-nine thousand, seven hundred five".