2103781689 has 9 divisors (see below), whose sum is σ = 3038994543. Its totient is φ = 1402429392.

The previous prime is 2103781657. The next prime is 2103781717. The reversal of 2103781689 is 9861873012.

The square root of 2103781689 is 45867.

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

2103781689 is a `hidden beast` number, since 210 + 378 + 1 + 68 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1315295289 + 788486400 = 36267^2 + 28080^2 .

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

It is not a de Polignac number, because 2103781689 - 2⁵ = 2103781657 is a prime.

It is a super-3 number, since 3×2103781689³ (a number of 29 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (2103781609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 129957 + ... + 145245.

Almost surely, 2^2103781689 is an apocalyptic number.

2103781689 is the 45867-th square number.

2103781689 is the 22934-th centered octagonal number.

It is an amenable number.

2103781689 is a deficient number, since it is larger than the sum of its proper divisors (935212854).

2103781689 is an frugal number, since it uses more digits than its factorization.

2103781689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30584 (or 15292 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The cubic root of 2103781689 is about 1281.3473948442.

The spelling of 2103781689 in words is "two billion, one hundred three million, seven hundred eighty-one thousand, six hundred eighty-nine".