19956774905 has 16 divisors (see below), whose sum is σ = 24180327360. Its totient is φ = 15810725952.

The previous prime is 19956774889. The next prime is 19956774917. The reversal of 19956774905 is 50947765991.

It is a cyclic number.

It is not a de Polignac number, because 19956774905 - 2⁴ = 19956774889 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2317067 + ... + 2325663.

It is an arithmetic number, because the mean of its divisors is an integer number (1511270460).

Almost surely, 2^19956774905 is an apocalyptic number.

It is an amenable number.

19956774905 is a deficient number, since it is larger than the sum of its proper divisors (4223552455).

19956774905 is a wasteful number, since it uses less digits than its factorization.

19956774905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13048.

The product of its (nonzero) digits is 21432600, while the sum is 62.

It can be divided in two parts, 199567 and 74905, that added together give a palindrome (274472).

The spelling of 19956774905 in words is "nineteen billion, nine hundred fifty-six million, seven hundred seventy-four thousand, nine hundred five".