1909948779 has 12 divisors (see below), whose sum is σ = 2759347032. Its totient is φ = 1273053600.

The previous prime is 1909948771. The next prime is 1909948801. The reversal of 1909948779 is 9778499091.

It is not a de Polignac number, because 1909948779 - 2³ = 1909948771 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1909948771) 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 11 ways as a sum of consecutive naturals, for example, 37399 + ... + 72239.

It is an arithmetic number, because the mean of its divisors is an integer number (229945586).

Almost surely, 2^1909948779 is an apocalyptic number.

1909948779 is a deficient number, since it is larger than the sum of its proper divisors (849398253).

1909948779 is a wasteful number, since it uses less digits than its factorization.

1909948779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40938 (or 40935 counting only the distinct ones).

The product of its (nonzero) digits is 10287648, while the sum is 63.

The square root of 1909948779 is about 43702.9607578251. The cubic root of 1909948779 is about 1240.7203538593.

The spelling of 1909948779 in words is "one billion, nine hundred nine million, nine hundred forty-eight thousand, seven hundred seventy-nine".