1909409040 has 720 divisors, whose sum is σ = 8397462528. Its totient is φ = 380160000.

The previous prime is 1909409017. The next prime is 1909409041. The reversal of 1909409040 is 409049091.

1909409040 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1909408986 and 1909409004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1909409041) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 18904990 + ... + 18905090.

Almost surely, 2^1909409040 is an apocalyptic number.

1909409040 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 1909409040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4198731264).

1909409040 is an abundant number, since it is smaller than the sum of its proper divisors (6488053488).

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

1909409040 is a wasteful number, since it uses less digits than its factorization.

1909409040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180 (or 160 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 1909409040 is about 43696.7852364450. The cubic root of 1909409040 is about 1240.6034697032.

The spelling of 1909409040 in words is "one billion, nine hundred nine million, four hundred nine thousand, forty".