16520221701 has 16 divisors (see below), whose sum is σ = 24500560000. Its totient is φ = 11001710304.

The previous prime is 16520221673. The next prime is 16520221787. The reversal of 16520221701 is 10712202561.

16520221701 is a `hidden beast` number, since 1 + 652 + 0 + 2 + 2 + 1 + 7 + 0 + 1 = 666.

It is not a de Polignac number, because 16520221701 - 2¹⁵ = 16520188933 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16520221001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 301201 + ... + 351798.

It is an arithmetic number, because the mean of its divisors is an integer number (1531285000).

Almost surely, 2^16520221701 is an apocalyptic number.

It is an amenable number.

16520221701 is a deficient number, since it is larger than the sum of its proper divisors (7980338299).

16520221701 is an equidigital number, since it uses as much as digits as its factorization.

16520221701 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 653945 (or 653939 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 27.

The spelling of 16520221701 in words is "sixteen billion, five hundred twenty million, two hundred twenty-one thousand, seven hundred one".