845821720 has 16 divisors (see below), whose sum is σ = 1903098960. Its totient is φ = 338328672.

The previous prime is 845821703. The next prime is 845821733. The reversal of 845821720 is 27128548.

It is a self number, because there is not a number n which added to its sum of digits gives 845821720.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10572732 + ... + 10572811.

It is an arithmetic number, because the mean of its divisors is an integer number (118943685).

Almost surely, 2^845821720 is an apocalyptic number.

It is an amenable number.

845821720 is an abundant number, since it is smaller than the sum of its proper divisors (1057277240).

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

845821720 is a wasteful number, since it uses less digits than its factorization.

845821720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21145554 (or 21145550 counting only the distinct ones).

The product of its (nonzero) digits is 35840, while the sum is 37.

The square root of 845821720 is about 29083.0142866932. The cubic root of 845821720 is about 945.7135489639.

The spelling of 845821720 in words is "eight hundred forty-five million, eight hundred twenty-one thousand, seven hundred twenty".