2109781505 has 32 divisors (see below), whose sum is σ = 2782080000. Its totient is φ = 1526533632.

The previous prime is 2109781469. The next prime is 2109781571. The reversal of 2109781505 is 5051879012.

It is not a de Polignac number, because 2109781505 - 2¹⁰ = 2109780481 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 701996 + ... + 704994.

It is an arithmetic number, because the mean of its divisors is an integer number (86940000).

Almost surely, 2^2109781505 is an apocalyptic number.

It is an amenable number.

2109781505 is a deficient number, since it is larger than the sum of its proper divisors (672298495).

2109781505 is a wasteful number, since it uses less digits than its factorization.

2109781505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3233.

The product of its (nonzero) digits is 25200, while the sum is 38.

The square root of 2109781505 is about 45932.3579298951. The cubic root of 2109781505 is about 1282.5643385704.

The spelling of 2109781505 in words is "two billion, one hundred nine million, seven hundred eighty-one thousand, five hundred five".