19756981459 has 4 divisors (see below), whose sum is σ = 19889578800. Its totient is φ = 19624384120.

The previous prime is 19756981421. The next prime is 19756981469. The reversal of 19756981459 is 95418965791.

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

It is a cyclic number.

It is not a de Polignac number, because 19756981459 - 2⁷ = 19756981331 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19756981459.

It is not an unprimeable number, because it can be changed into a prime (19756981469) 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, 66298447 + ... + 66298744.

It is an arithmetic number, because the mean of its divisors is an integer number (4972394700).

Almost surely, 2^19756981459 is an apocalyptic number.

19756981459 is a deficient number, since it is larger than the sum of its proper divisors (132597341).

19756981459 is a wasteful number, since it uses less digits than its factorization.

19756981459 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132597340.

The product of its digits is 24494400, while the sum is 64.

The spelling of 19756981459 in words is "nineteen billion, seven hundred fifty-six million, nine hundred eighty-one thousand, four hundred fifty-nine".