19928126077 has 4 divisors (see below), whose sum is σ = 19935572956. Its totient is φ = 19920679200.

The previous prime is 19928126059. The next prime is 19928126093. The reversal of 19928126077 is 77062182991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 77062182991 = 149 ⋅517195859.

It can be written as a sum of positive squares in 2 ways, for example, as 10194133156 + 9733992921 = 100966^2 + 98661^2 .

It is a cyclic number.

It is not a de Polignac number, because 19928126077 - 2²³ = 19919737469 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 (19928126047) 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, 3719424 + ... + 3724777.

It is an arithmetic number, because the mean of its divisors is an integer number (4983893239).

Almost surely, 2^19928126077 is an apocalyptic number.

It is an amenable number.

19928126077 is a deficient number, since it is larger than the sum of its proper divisors (7446879).

19928126077 is an equidigital number, since it uses as much as digits as its factorization.

19928126077 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7446878.

The product of its (nonzero) digits is 762048, while the sum is 52.

The spelling of 19928126077 in words is "nineteen billion, nine hundred twenty-eight million, one hundred twenty-six thousand, seventy-seven".