20354945405 has 4 divisors (see below), whose sum is σ = 24425934492. Its totient is φ = 16283956320.

The previous prime is 20354945381. The next prime is 20354945407. The reversal of 20354945405 is 50454945302.

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 16093205881 + 4261739524 = 126859^2 + 65282^2 .

It is a de Polignac number, because none of the positive numbers 2^k-20354945405 is a prime.

It is a super-2 number, since 2×20354945405² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20354945407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2035494536 + ... + 2035494545.

It is an arithmetic number, because the mean of its divisors is an integer number (6106483623).

Almost surely, 2^20354945405 is an apocalyptic number.

It is an amenable number.

20354945405 is a deficient number, since it is larger than the sum of its proper divisors (4070989087).

20354945405 is an equidigital number, since it uses as much as digits as its factorization.

20354945405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4070989086.

The product of its (nonzero) digits is 432000, while the sum is 41.

The spelling of 20354945405 in words is "twenty billion, three hundred fifty-four million, nine hundred forty-five thousand, four hundred five".