16521220140 has 24 divisors (see below), whose sum is σ = 46259416560. Its totient is φ = 4405658688.

The previous prime is 16521220123. The next prime is 16521220159. The reversal of 16521220140 is 4102212561.

It is a self number, because there is not a number n which added to its sum of digits gives 16521220140.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 137676775 + ... + 137676894.

It is an arithmetic number, because the mean of its divisors is an integer number (1927475690).

Almost surely, 2^16521220140 is an apocalyptic number.

16521220140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16521220140 is an abundant number, since it is smaller than the sum of its proper divisors (29738196420).

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

16521220140 is a wasteful number, since it uses less digits than its factorization.

16521220140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 275353681 (or 275353679 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

The spelling of 16521220140 in words is "sixteen billion, five hundred twenty-one million, two hundred twenty thousand, one hundred forty".