865945920 has 112 divisors (see below), whose sum is σ = 3142171008. Its totient is φ = 197928960.

The previous prime is 865945897. The next prime is 865945931. The reversal of 865945920 is 29549568.

It is a tau number, because it is divible by the number of its divisors (112).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 865945920.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57711 + ... + 71150.

Almost surely, 2^865945920 is an apocalyptic number.

865945920 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

865945920 is an abundant number, since it is smaller than the sum of its proper divisors (2276225088).

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

865945920 is a wasteful number, since it uses less digits than its factorization.

865945920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128888 (or 128878 counting only the distinct ones).

The product of its (nonzero) digits is 777600, while the sum is 48.

The square root of 865945920 is about 29426.9590681742. The cubic root of 865945920 is about 953.1551310299.

The spelling of 865945920 in words is "eight hundred sixty-five million, nine hundred forty-five thousand, nine hundred twenty".