16064721 has 12 divisors (see below), whose sum is σ = 23241348. Its totient is φ = 10692864.

The previous prime is 16064707. The next prime is 16064723. The reversal of 16064721 is 12746061.

16064721 is a `hidden beast` number, since 16 + 0 + 647 + 2 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 2822400 + 13242321 = 1680^2 + 3639^2 .

It is not a de Polignac number, because 16064721 - 2⁵ = 16064689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16064723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7641 + ... + 9513.

It is an arithmetic number, because the mean of its divisors is an integer number (1936779).

Almost surely, 2^16064721 is an apocalyptic number.

It is an amenable number.

16064721 is a deficient number, since it is larger than the sum of its proper divisors (7176627).

16064721 is a wasteful number, since it uses less digits than its factorization.

16064721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2832 (or 2829 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 16064721 is about 4008.0819602398. The cubic root of 16064721 is about 252.3235168430.

The spelling of 16064721 in words is "sixteen million, sixty-four thousand, seven hundred twenty-one".