1820528640 has 624 divisors, whose sum is σ = 7728110208. Its totient is φ = 386924544.

The previous prime is 1820528579. The next prime is 1820528653. The reversal of 1820528640 is 468250281.

1820528640 is a `hidden beast` number, since 1 + 8 + 2 + 0 + 5 + 2 + 8 + 640 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct 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 = 1820528595 and 1820528604.

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, 21934039 + ... + 21934121.

It is an arithmetic number, because the mean of its divisors is an integer number (12384792).

Almost surely, 2^1820528640 is an apocalyptic number.

1820528640 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 1820528640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3864055104).

1820528640 is an abundant number, since it is smaller than the sum of its proper divisors (5907581568).

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

1820528640 is a wasteful number, since it uses less digits than its factorization.

1820528640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The square root of 1820528640 is about 42667.6533219253. The cubic root of 1820528640 is about 1221.0473492898.

The spelling of 1820528640 in words is "one billion, eight hundred twenty million, five hundred twenty-eight thousand, six hundred forty".