16620747521 has 12 divisors (see below), whose sum is σ = 19336638960. Its totient is φ = 14244660360.

The previous prime is 16620747503. The next prime is 16620747547. The reversal of 16620747521 is 12574702661.

It is not a de Polignac number, because 16620747521 - 2¹⁰ = 16620746497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16620747551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 570806 + ... + 599216.

It is an arithmetic number, because the mean of its divisors is an integer number (1611386580).

Almost surely, 2^16620747521 is an apocalyptic number.

It is an amenable number.

16620747521 is a deficient number, since it is larger than the sum of its proper divisors (2715891439).

16620747521 is a wasteful number, since it uses less digits than its factorization.

16620747521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40364 (or 40357 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 41.

The spelling of 16620747521 in words is "sixteen billion, six hundred twenty million, seven hundred forty-seven thousand, five hundred twenty-one".