1905344640 has 256 divisors, whose sum is σ = 6847545600. Its totient is φ = 500613120.

The previous prime is 1905344629. The next prime is 1905344659. The reversal of 1905344640 is 464435091.

1905344640 is a `hidden beast` number, since 1 + 9 + 0 + 5 + 3 + 4 + 4 + 640 = 666.

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 = 1905344595 and 1905344604.

It is a congruent number.

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, 1226104 + ... + 1227656.

It is an arithmetic number, because the mean of its divisors is an integer number (26748225).

Almost surely, 2^1905344640 is an apocalyptic number.

1905344640 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 1905344640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3423772800).

1905344640 is an abundant number, since it is smaller than the sum of its proper divisors (4942200960).

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

1905344640 is a wasteful number, since it uses less digits than its factorization.

1905344640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1652 (or 1634 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 1905344640 is about 43650.2536075107. The cubic root of 1905344640 is about 1239.7225879595.

The spelling of 1905344640 in words is "one billion, nine hundred five million, three hundred forty-four thousand, six hundred forty".