845205840 has 400 divisors, whose sum is σ = 3150119808. Its totient is φ = 209544192.

The previous prime is 845205839. The next prime is 845205883. The reversal of 845205840 is 48502548.

845205840 is a `hidden beast` number, since 84 + 520 + 58 + 4 + 0 = 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 = 845205795 and 845205804.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 7899067 + ... + 7899173.

Almost surely, 2^845205840 is an apocalyptic number.

845205840 is a gapful number since it is divisible by the number (80) 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 845205840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1575059904).

845205840 is an abundant number, since it is smaller than the sum of its proper divisors (2304913968).

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

845205840 is a wasteful number, since it uses less digits than its factorization.

845205840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208 (or 193 counting only the distinct ones).

The product of its (nonzero) digits is 51200, while the sum is 36.

The square root of 845205840 is about 29072.4240475403. The cubic root of 845205840 is about 945.4839546841.

The spelling of 845205840 in words is "eight hundred forty-five million, two hundred five thousand, eight hundred forty".