1864304640 has 384 divisors, whose sum is σ = 7241270400. Its totient is φ = 451215360.

The previous prime is 1864304599. The next prime is 1864304641. The reversal of 1864304640 is 464034681.

1864304640 is a `hidden beast` number, since 1 + 8 + 6 + 4 + 3 + 0 + 4 + 640 = 666.

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 (36).

It is a junction number, because it is equal to n+sod(n) for n = 1864304595 and 1864304604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1864304641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3040974 + ... + 3041586.

It is an arithmetic number, because the mean of its divisors is an integer number (18857475).

Almost surely, 2^1864304640 is an apocalyptic number.

1864304640 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 1864304640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3620635200).

1864304640 is an abundant number, since it is smaller than the sum of its proper divisors (5376965760).

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

1864304640 is a wasteful number, since it uses less digits than its factorization.

1864304640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660 (or 634 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The square root of 1864304640 is about 43177.5941895794. The cubic root of 1864304640 is about 1230.7569403901.

The spelling of 1864304640 in words is "one billion, eight hundred sixty-four million, three hundred four thousand, six hundred forty".