29985865520 has 80 divisors (see below), whose sum is σ = 75131878752. Its totient is φ = 11064053760.

The previous prime is 29985865517. The next prime is 29985865529. The reversal of 29985865520 is 2556858992.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 29985865520.

It is not an unprimeable number, because it can be changed into a prime (29985865529) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1624664 + ... + 1643016.

Almost surely, 2^29985865520 is an apocalyptic number.

29985865520 is a gapful number since it is divisible by the number (20) 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 29985865520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37565939376).

29985865520 is an abundant number, since it is smaller than the sum of its proper divisors (45146013232).

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

29985865520 is a wasteful number, since it uses less digits than its factorization.

29985865520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19950 (or 19944 counting only the distinct ones).

The product of its (nonzero) digits is 15552000, while the sum is 59.

The spelling of 29985865520 in words is "twenty-nine billion, nine hundred eighty-five million, eight hundred sixty-five thousand, five hundred twenty".