19826077405 has 4 divisors (see below), whose sum is σ = 23791292892. Its totient is φ = 15860861920.

The previous prime is 19826077387. The next prime is 19826077423. The reversal of 19826077405 is 50477062891.

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

It is an interprime number because it is at equal distance from previous prime (19826077387) and next prime (19826077423).

It can be written as a sum of positive squares in 2 ways, for example, as 12343654404 + 7482423001 = 111102^2 + 86501^2 .

It is a de Polignac number, because none of the positive numbers 2^k-19826077405 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 1982607736 + ... + 1982607745.

It is an arithmetic number, because the mean of its divisors is an integer number (5947823223).

Almost surely, 2^19826077405 is an apocalyptic number.

It is an amenable number.

19826077405 is a deficient number, since it is larger than the sum of its proper divisors (3965215487).

19826077405 is an equidigital number, since it uses as much as digits as its factorization.

19826077405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3965215486.

The product of its (nonzero) digits is 846720, while the sum is 49.

The spelling of 19826077405 in words is "nineteen billion, eight hundred twenty-six million, seventy-seven thousand, four hundred five".