9985805040 has 80 divisors (see below), whose sum is σ = 30967767936. Its totient is φ = 2661868800.

The previous prime is 9985805023. The next prime is 9985805069. The reversal of 9985805040 is 405085899.

It is a happy number.

It is a Cunningham number, because it is equal to 99929²-1.

It is a tau number, because it is divible by the number of its divisors (80).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 793195 + ... + 805685.

Almost surely, 2^9985805040 is an apocalyptic number.

It is an amenable number.

9985805040 is an abundant number, since it is smaller than the sum of its proper divisors (20981962896).

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

9985805040 is a wasteful number, since it uses less digits than its factorization.

9985805040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15838 (or 15832 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 48.

The square root of 9985805040 is about 99928.9999949964. Note that the first 5 decimals coincide. The cubic root of 9985805040 is about 2153.4148034963.

The spelling of 9985805040 in words is "nine billion, nine hundred eighty-five million, eight hundred five thousand, forty".