19992661783 has 4 divisors (see below), whose sum is σ = 21044907160. Its totient is φ = 18940416408.

The previous prime is 19992661781. The next prime is 19992661811. The reversal of 19992661783 is 38716629991.

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 19992661783 - 2¹ = 19992661781 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 (19992661781) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 526122660 + ... + 526122697.

It is an arithmetic number, because the mean of its divisors is an integer number (5261226790).

Almost surely, 2^19992661783 is an apocalyptic number.

19992661783 is a deficient number, since it is larger than the sum of its proper divisors (1052245377).

19992661783 is a wasteful number, since it uses less digits than its factorization.

19992661783 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1052245376.

The product of its digits is 8817984, while the sum is 61.

The spelling of 19992661783 in words is "nineteen billion, nine hundred ninety-two million, six hundred sixty-one thousand, seven hundred eighty-three".