16630939521 has 135 divisors (see below), whose sum is σ = 30554282451. Its totient is φ = 8988065856.

The previous prime is 16630939477. The next prime is 16630939541. The reversal of 16630939521 is 12593903661.

The square root of 16630939521 is 128961.

It is a perfect power (a square), and thus also a powerful number.

16630939521 is a `hidden beast` number, since 1 + 6 + 6 + 30 + 93 + 9 + 521 = 666.

It can be written as a sum of positive squares in only one way, i.e., 3193493121 + 13437446400 = 56511^2 + 115920^2 .

It is not a de Polignac number, because 16630939521 - 2³³ = 8041004929 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16630939541) 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 134 ways as a sum of consecutive naturals, for example, 186864445 + ... + 186864533.

Almost surely, 2^16630939521 is an apocalyptic number.

16630939521 is the 128961-st square number.

16630939521 is the 64481-st centered octagonal number.

It is an amenable number.

16630939521 is a deficient number, since it is larger than the sum of its proper divisors (13923342930).

16630939521 is an frugal number, since it uses more digits than its factorization.

16630939521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 262440, while the sum is 45.

The spelling of 16630939521 in words is "sixteen billion, six hundred thirty million, nine hundred thirty-nine thousand, five hundred twenty-one".