16790721 has 4 divisors (see below), whose sum is σ = 22387632. Its totient is φ = 11193812.

The previous prime is 16790717. The next prime is 16790729. The reversal of 16790721 is 12709761.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 16790721 - 2² = 16790717 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16790729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2798451 + ... + 2798456.

It is an arithmetic number, because the mean of its divisors is an integer number (5596908).

Almost surely, 2^16790721 is an apocalyptic number.

It is an amenable number.

16790721 is a deficient number, since it is larger than the sum of its proper divisors (5596911).

16790721 is an equidigital number, since it uses as much as digits as its factorization.

16790721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5596910.

The product of its (nonzero) digits is 5292, while the sum is 33.

The square root of 16790721 is about 4097.6482279473. The cubic root of 16790721 is about 256.0686715594.

The spelling of 16790721 in words is "sixteen million, seven hundred ninety thousand, seven hundred twenty-one".