16520165662725 has 36 divisors (see below), whose sum is σ = 29591249091300. Its totient is φ = 8810219988480.

The previous prime is 16520165662717. The next prime is 16520165662729. The reversal of 16520165662725 is 52726656102561.

16520165662725 is a `hidden beast` number, since 1 + 6 + 5 + 2 + 0 + 1 + 6 + 5 + 6 + 627 + 2 + 5 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 1001348454276 + 15518817208449 = 1000674^2 + 3939393^2 .

It is not a de Polignac number, because 16520165662725 - 2³ = 16520165662717 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16520165662729) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1497991 + ... + 5940059.

It is an arithmetic number, because the mean of its divisors is an integer number (821979141425).

Almost surely, 2^{16520165662725} is an apocalyptic number.

16520165662725 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

16520165662725 is a deficient number, since it is larger than the sum of its proper divisors (13071083428575).

16520165662725 is a wasteful number, since it uses less digits than its factorization.

16520165662725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4458614 (or 4458606 counting only the distinct ones).

The product of its (nonzero) digits is 9072000, while the sum is 54.

The spelling of 16520165662725 in words is "sixteen trillion, five hundred twenty billion, one hundred sixty-five million, six hundred sixty-two thousand, seven hundred twenty-five".