1909729920 has 384 divisors, whose sum is σ = 7233546240. Its totient is φ = 427155456.

The previous prime is 1909729909. The next prime is 1909729937. The reversal of 1909729920 is 299279091.

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 1909729920.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4986049 + ... + 4986431.

It is an arithmetic number, because the mean of its divisors is an integer number (18837360).

Almost surely, 2^1909729920 is an apocalyptic number.

1909729920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1909729920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3616773120).

1909729920 is an abundant number, since it is smaller than the sum of its proper divisors (5323816320).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1909729920 is a wasteful number, since it uses less digits than its factorization.

1909729920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 472 (or 453 counting only the distinct ones).

The product of its (nonzero) digits is 183708, while the sum is 48.

The square root of 1909729920 is about 43700.4567481851. The cubic root of 1909729920 is about 1240.6729611069.

The spelling of 1909729920 in words is "one billion, nine hundred nine million, seven hundred twenty-nine thousand, nine hundred twenty".