16720387 has 8 divisors (see below), whose sum is σ = 17100720. Its totient is φ = 16342560.

The previous prime is 16720369. The next prime is 16720409. The reversal of 16720387 is 78302761.

16720387 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16720387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16720307) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20212 + ... + 21022.

It is an arithmetic number, because the mean of its divisors is an integer number (2137590).

Almost surely, 2^16720387 is an apocalyptic number.

16720387 is a deficient number, since it is larger than the sum of its proper divisors (380333).

16720387 is an equidigital number, since it uses as much as digits as its factorization.

16720387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1253.

The product of its (nonzero) digits is 14112, while the sum is 34.

The square root of 16720387 is about 4089.0569817502. The cubic root of 16720387 is about 255.7106257827.

The spelling of 16720387 in words is "sixteen million, seven hundred twenty thousand, three hundred eighty-seven".