4072191921 has 16 divisors (see below), whose sum is σ = 6894716800. Its totient is φ = 2326966704.

The previous prime is 4072191913. The next prime is 4072191941. The reversal of 4072191921 is 1291912704.

4072191921 is a `hidden beast` number, since 407 + 219 + 19 + 21 = 666.

It is not a de Polignac number, because 4072191921 - 2³ = 4072191913 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (4072191901) 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 15 ways as a sum of consecutive naturals, for example, 10772806 + ... + 10773183.

It is an arithmetic number, because the mean of its divisors is an integer number (430919800).

Almost surely, 2^4072191921 is an apocalyptic number.

It is an amenable number.

4072191921 is a deficient number, since it is larger than the sum of its proper divisors (2822524879).

4072191921 is a wasteful number, since it uses less digits than its factorization.

4072191921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21546005 (or 21545999 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 4072191921 is about 63813.7283113908. The cubic root of 4072191921 is about 1596.8939639528.

The spelling of 4072191921 in words is "four billion, seventy-two million, one hundred ninety-one thousand, nine hundred twenty-one".