19954786387 has 16 divisors (see below), whose sum is σ = 21229992000. Its totient is φ = 18728962560.

The previous prime is 19954786373. The next prime is 19954786393. The reversal of 19954786387 is 78368745991.

It is a cyclic number.

It is not a de Polignac number, because 19954786387 - 2⁷ = 19954786259 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19954786487) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 61114 + ... + 208912.

It is an arithmetic number, because the mean of its divisors is an integer number (1326874500).

Almost surely, 2^19954786387 is an apocalyptic number.

19954786387 is a deficient number, since it is larger than the sum of its proper divisors (1275205613).

19954786387 is a wasteful number, since it uses less digits than its factorization.

19954786387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147966.

The product of its digits is 91445760, while the sum is 67.

The spelling of 19954786387 in words is "nineteen billion, nine hundred fifty-four million, seven hundred eighty-six thousand, three hundred eighty-seven".