1019992942809 has 9 divisors (see below), whose sum is σ = 1473327516063. Its totient is φ = 679993275312.

The previous prime is 1019992942783. The next prime is 1019992942823. The reversal of 1019992942809 is 9082492999101.

The square root of 1019992942809 is 1009947.

It is a perfect power (a square), and thus also a powerful number.

1019992942809 is a `hidden beast` number, since 10 + 199 + 9 + 2 + 9 + 428 + 0 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 819754592409 + 200238350400 = 905403^2 + 447480^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 1019992942809 - 2¹⁹ = 1019992418521 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1019992940809) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2861517 + ... + 3198165.

Almost surely, 2^{1019992942809} is an apocalyptic number.

1019992942809 is the 1009947-th square number.

1019992942809 is the 504974-th centered octagonal number.

It is an amenable number.

1019992942809 is a deficient number, since it is larger than the sum of its proper divisors (453334573254).

1019992942809 is an frugal number, since it uses more digits than its factorization.

1019992942809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 673304 (or 336652 counting only the distinct ones).

The product of its (nonzero) digits is 7558272, while the sum is 63.

It can be divided in two parts, 1019992 and 942809, that added together give a square (1962801 = 1401²).

The spelling of 1019992942809 in words is "one trillion, nineteen billion, nine hundred ninety-two million, nine hundred forty-two thousand, eight hundred nine".